PHENOLOGY AND SEED QUALITY RESPONSE OF RAPE (B. NAPUS) VERSUS MUSTARD (B. JUNCEA) TO SULFUR AND POTASSIUM FERTILIZATION IN NORTHWEST PAKISTAN

Inappropriate sulfur and potassium fertilization, particularly with continued soil nutrient mining and yearly fluctuations in rainfall, are major factors contributing to slow growth and low seed quality of canola in northwestern Pakistan. A field experiment was conducted in 2007–2008 on a sulfur (S) and potassium (K) deficient clay loam soil under irrigation at the research farm of NWFP (Northwest Frontier Province) Agricultural University, Peshawar, Pakistan, with an objective to determine response of phenology and seed quality of Brassica oilseed rape versus mustard to S and K fertilizer application. Twenty treatments in a randomized complete block design were consisted of two oilseed genotypes [rape (B. napus canola) and mustard (B. juncea canola)], at three rates each of S (15, 30, and 45 kg S ha^?1) and K (30, 60, and 90 kg K ha^?1), plus control (no K and S applied). Days to flowering, pod formation, seed filling duration and maturity were enhanced with K and S fertilization compared to control plots. The species B. napus took more time to flowering, pod formation, seed filling duration and maturity compared to B. juncea. Both genotypes responded positively for seed quality (oil and protein content) to K and S fertilization, but the magnitude of response varied with level and combination of K and S fertilization. Delay in the phenological stages showed negative relationship with oil and protein content in seed of both genotypes. It is concluded that a combination of 60 kg K ha^?1 + 30 kg S ha^?1 would accelerate phenological development and improve seed quality of rape and mustard in the study area.     

Potassium‐fertilizer management in winter oilseed‐rape production in China

Optimal potassium (K) fertilization is beneficial for oilseed‐rape (Brassica napus L.) yield and quality. However, the discrepancy between the high K demand of winter oilseed rape and low soil fertility and insufficient potassium input has limited the sustainable development of oilseed‐rape production. A series of on‐farm experiments in the key winter oilseed‐rape domains of China was conducted from 2004 to 2010 to evaluate K‐fertilizer management for winter oilseed rape. Currently, the average NH₄OAc‐extractable K content in the 0–20 cm soil layer is 89.1 mg kg^–1 indicative of “slight deficiency”. In addition, farmers in China usually fail to use sufficient K fertilizer in oilseed‐rape production, the average mineral‐potassium‐fertilizer input in 2010 being only 35 kg K ha^–1, far lower than the recommended rate of potassium for winter oilseed rape. Adequate potassium fertilization significantly raises seed yield. The average yield‐increase rate for the major production regions due to K‐fertilizer application was 18.5%, and the average K fertilizer–use efficiency 36.1%. Based on the negative correlation between yield response to potassium fertilization and available soil K content, a soil‐K‐test index was established for winter oilseed rape with a threshold value for NH₄OAc‐extractable soil K of 135 mg kg^–1. When available soil K‐content is below this threshold value, more K fertilizer should be applied to achieve high seed yield and to increase soil fertility. The major challenge for K‐fertilizer management in winter oilseed‐rape production in China will be to guide farmers in the different regions in making reasonable use of K fertilizer through soil K‐testing technology in order to maintain both seed yield and soil fertility.     

EFFECTS OF CONVENTIONAL AND CONTROLLED RELEASE PHOSPHORUS FERTILIZER ON CROP EMERGENCE AND GROWTH RESPONSE UNDER CONTROLLED ENVIRONMENT CONDITIONS

A series of experiments on the effects of form and rate of seed row placed phosphorus (P) fertilizer were carried out under controlled environment conditions using flats of a P-deficient Brown Chernozemic soil from Saskatchewan, Canada. The experiments were conducted in the laboratory and growth chamber using rates of seed row placed granular P fertilizer up to 100 kg P₂O₅ ha^?1. Two forms of monoammonium phosphate fertilizer were compared: 1) conventional MAP granules and 2) controlled release phosphorus (CRP) fertilizer granules (Agrium Inc, Denver, CO, USA.) made with a polymer coating to slow the release of phosphate to soil solution. Six crops were utilized in the study to provide a range of commonly grown cereal, oilseed, pulse and forage crops in Western Canada: wheat (Triticum aestivum), canola (Brassica napus), mustard (Brassica juncea), flax (Linum usitatissimum), yellow pea (Pisum sativum) and alfalfa (Medicago sativum). Parameters measured were percentage of planted seeds that had emerged after two weeks, plant biomass yield, and plant P uptake after four weeks. Most of the crops tested showed no negative impact on emergence with seed row placed conventional P fertilizer at rates up to ～20 to 30 kg P₂O₅ ha^?1. Pea, flax and mustard tended to be most sensitive to injury from high rates of seed placed MAP while wheat was least sensitive. The controlled release phosphorus fertilizer (CRP) product greatly increased the tolerance of crops to high rates of seed row placed P, with rates of 80 kg P₂O₅ ha^?1 placed in the seed row producing no significant injury for most crops. This effect is attributed to the coating reducing the harmful salt effect that occurs when high rates of fertilizer are placed in the seed row in close proximity to the seed. Generally, a rate of 30 kg P₂O₅ ha^?1 was sufficient to produce maximum early season biomass yield and P uptake for both conventional MAP and CRP fertilizers. Large differences in early P availability were not evident between the conventional P and controlled released P fertilizer products.     

轮作体系下冬油菜养分利用效率的区域研究

Fertilization is essential for oilseed rape because it is sensitivity to nutrient deficiency, especially for winter oilseed rape(Brassica napus L.). To investigate regional nutrient efficiency and nutrient uptake-yield relationship of winter oilseed rape in an intensive cropping system, this study used data from 619 site-year on-farm experiments carried out in the winter oilseed rape planting area of the Yangtze River Basin, China from 2005 to 2010, with large yield in the range of 179–4 470 kg ha~(-1). Currently recommended application rates of N, P and K fertilizers increased rapeseed yield at different levels of soil indigenous nutrient supply(INS) in this region. Boundary values of plant nutrient uptake were established to analyze the nutrient uptake-yield relationship of winter oilseed rape(internal nutrient efficiency), i.e., 128 kg N ha~(-1), 24 kg P ha~(-1), and 122 kg K ha~(-1). The internal nutrient efficiency declined by 48.2%–64.1% when nutrient uptake exceeded the boundary value, resulting in excessive nutrient uptake(i.e., low yield response with high nutrient uptake), especially for K. In the intensive cropping system, agronomic efficiencies of N, P, and K were 5.9, 3.4, and3.6 kg kg~(-1), and recovery efficiencies of N, P, and K were 35.6%, 24.1%, and 36.8%, respectively. These findings showed that the fertilization rate should be optimized by considering INS, nutrient status, and nutrient efficiency of winter oilseed rape. In this study,considering the lower yield improvement to high K uptake levels and low K fertilizer efficiency, application rate of K fertilizer should be reduced since soil K deficiency has already been mitigated.     

INTERACTIVE EFFECT OF SULFUR AND NITROGEN ON GROWTH AND YIELD ATTRIBUTES OF OILSEED CROPS (BRASSICA CAMPESTRIS L. AND ERUCA SATIVA MILL.) DIFFERING IN YIELD POTENTIAL

Field experiments were conducted to determine the interactive effect of sulfur (S) and nitrogen (N) on growth and yield attributes of oilseed crops [Brassica campestris L. (V₁) and Eruca sativa Mill. (V₂)] differing in yield potential. Two combinations of S and N (in kg ha^?1): 0S + 100N (?S+N;T₁) and 40S + 100N (+S+N;T₂) were used. Biomass accumulation, leaf area index (LAI), leaf area duration (LAD), and photosynthetic rate in the leaves were determined at various phenological stages. The results showed that the combined application of S and N (+S+N) significantly (P<0.05) improved the growth and yield attributes of both the genotypes compared with N applied alone (?S+N). Genetic variability was observed between the two genotypes in response to combined application of S and N (T₂). Genotype V₁ had higher biomass accumulation, photosynthetic rate, seed yield, oil yield, biological yield, and harvest index when compared with genotype V₂. Treatment T₂ resulted in 142, 95, 56, and 349% enhancement in biomass accumulation, leaf-area index (LAI), leaf-area duration (LAD) and photosynthetic rate, respectively in comparison with treatment T₁ in genotype V₁. Seed yield, oil yield, biological yield, and harvest index were improved by 141, 171, 85, and 30%, respectively, by treatment T₂ in comparison with T₁. In the case of genotype V₂, increase in biomass accumulation, LAI, LAD, and photosynthetic rate due to application of treatment T₂ were 156, 137, 125 and 467%, respectively, over the results of T₁. Seed yield, oil yield, biological yield and harvest index improved by 193, 251, 98, and 48%, respectively, with this treatment. On the basis of results obtained in this study, it can be concluded that sulfur must be included in the nutrient management package for optimum growth and yield attributes of oilseed crops. Furthermore, the yield potential of oilseed crops with low seed and oil yield can be improved using this treatment as achieved in our study in case of taramira (Eruca sativa Mill.), a genotype with low seed and oil yield.     

INFLUENCE OF NITROGEN AND SULFUR ON YIELD AND SEED QUALITY OF THREE CANOLA CULTIVARS

In order to investigate the effect of nitrogen (N) and sulfur (S) fertilizers on yield and seed quality of three canola cultivars, a factorial based on randomized complete block experiment was conducted during 2005–2006 in Iran. Treatments included four nitrogen rates (0, 75, 150, and 225 kg N ha^?1 source of urea), four sulfur rates (0, 100, 200, and 300 kg S ha^?1), and three cultivars (‘Pf’, ‘Option-500’, and ‘Hyola-401’). Results indicated cultivar had a significant effect on all studied traits. ‘Option-500’ and ‘Hyola-401’ cultivars had the highest seed yield, protein content, and N:S ratio in seed. The levels of 150 and 220 kg N ha^?1 resulted in the maximum protein content. Increasing N levels resulted in N content and decreased the oil content. The interaction effect between S and N levels showed the highest N content in seed was obtained with 300 kg S ha^?1 and 225 kg N ha^?1.     

Seasonal Biomass Accumulation and Nutrient Uptake of Canola,Mustard, and Flax on a Black Chernozem Soil in Saskatchewan

ABSTRACT

Seed yield and nutrient use efficiency are related to biomass accumulation and nutrient uptake in the growing season. Biomass accumulation and nutrient uptake of canola (Brassica napus L. and Brassica rapa L.), mustard (Brassica juncea L.) and flax (Linum usitatissimum L.) and the relationship to days after emergence (DAE) or growing degree days (GDD) were determined during the 1998 and 1999 growing seasons in field experiments at Melfort, Saskatchewan, Canada. In general, biomass accumulation and nutrient uptake increased with time at early growth stages and reached a maximum at late growth stages. Significant R² values for both biomass accumulation and nutrient uptake indicated that a cubic polynomial type equation was suitable to represent these parameters as a function of DAE. All oilseed crops maximized biomass at mid way to the end of pod forming stages (74–84 DAE or 750–973 GDD). Maximum biomass accumulation rate occurred at the early to late bud forming stage (42–49 DAE or 390–498 GDD), and it was 146–190 kg ha^?1d^?1 for canola, 158–182 kg ha^?1d^?1 for mustard, and 174–189 kg ha^?1d^?1 for flax. Maximum nutrient uptake occurred during flowering to early ripening (59–82 DAE or 597–945 GDD). Maximum nutrient uptake rate normally occurred at branching to early bud formation (21–42 DAE or 142–399 GDD). There was a close correlation between biomass accumulation and nutrient uptake, and among nutrients, suggesting interrelated absorption. For nitrogen (N), phosphorus (P), potassium (K), sulfur (S), and boron (B), respectively, maximum nutrient uptake rate was 2.3–4.5, 0.3–0.5, 2.5–5.7, 0.7–1.1, and 0.005–0.008 kg ha^?1d^?1 for canola; 2.3–3.9, 0.4–0.5, 2.6–4.9, 1.2–1.4, and 0.006–0.008 kg ha^?1d^?1 for mustard; and 3.2–4.0, 0.3–0.4, 2.9–4.1, 0.3–0.5, and 0.004–0.009 kg ha^?1d^?1 for flax. In general, maximum nutrient uptake rate and amount occurred earlier than maximum biomass accumulation rate and amount, and maximum rates of both nutrient uptake and biomass accumulation occurred earlier than their maximum amounts. The findings suggest that for high seed yields, there should be adequate supply of nutrients for plants, particularly to sustain high nutrient uptake rate at branching to bud forming stage and high biomass accumulation rate at early to late bud forming stage.     

Uptake and nutrient balance of nitrogen,sulfur, and boron for optimal canola production in eastern Canada

Balanced plant nutrition is essential to achieve high yields of canola (Brassica napus L.) and get the best economic return from applied fertilizers. A field study was conducted at nine site‐years across eastern Canada to investigate the effects of nitrogen (N), sulfur (S) and boron (B) fertilization on canola nutrient uptake, nutrient balance, and their relationship to canola yields. The factorial experiment consisted of four N rates of 0 (N0), 50 (N50), 100 (N100), and 150 (N150) kg ha^?1, two S rates of 0 (S0) and 20 (S20) kg ha^?1, and three B treatments of 0 (B0), 2 kg ha^?1 at preplant (B2.0P), and 0.5 kg B ha^?1 foliar‐applied at early flowering stage (B0.5F). Each site‐year used the same experimental design and assigned treatments in a randomized complete block design with four replications. Fertilizer S application greatly improved seed yields at six out of nine site‐years, and the highest N use efficiency was in the N150+S20 treatment. Sulfur application generally increased seed S concentration, seed S removal, and plant total S uptake, while B fertilization mainly elevated straw B concentration and content, with minimal effect on seed yields. At the early flowering stage, plant tissue S ranged from 2.2 to 6.6 mg S g^?1, but the N : S ratio was over or close to the critical value of 12 in the N150+S0 combination at five site‐years. On average across nine site‐years, canola reached a plateau yield of 3580 kg ha^?1 when plants contained 197 kg N ha^?1, 33 kg S ha^?1 and 200 g B ha^?1, with a seed B content of 60 g B ha^?1. The critical N, S, and B values identified in this work and their potential for a posteriori nutrient diagnosis of canola should be useful to validate fertilizer requirements for canola production in eastern Canada.     

EFFECT OF NITROGEN AND SULFUR FERTILIZATION ON YIELD COMPONENTS,SEED AND OIL YIELDS OF CANOLA

Field experiments were conducted to evaluate the effects of nitrogen (N) and sulfur (S) levels and their methods of application on canola. Branches plant^?1, pods plant^?1 and biological yield significantly increased with increase in nitrogen level and no significant increase in seed pod^?1 and seed and oil yields occurred beyond 120 kg N ha^?1. However, thousand seed weight consistently decreased with increasing level of nitrogen. Pods plant^?1 and biological yield continually increased with increase in sulfur level. Alternatively, significant increase in branches plant^?1, seed pod^?1, seed weight, seed and oil yields was noted with increase in sulfur level up to 40 kg ha^?1. Applications of sulfur and nitrogen in split significantly decreased seed yield as compared to sole applications. It is concluded that sulfur and nitrogen application as sole at the rate of 40 and 120 kg ha^?1, respectively performed better than the rest of their levels and method of application.     

Direct and Residual Effect of Sulphur Fertilization on Yield,Uptake and Use Efficiency in Indian Mustard and Succeeding Rice Crop

A field experiment was conducted on Indian mustard (Brassica juncea) with five levels of sulfur (S), 0, 15, 30, 45, and 60 kg S ha^?1 in sub-tropical Inceptisol of Jammu, North India. The residual effect of S on rice crop was evaluated. The seed and stover yield of mustard increased in the linear order up to 60 kg S ha^?1 but significant yield increase was obtained up to 30 S kg ha^?1 which was 21.4 percent higher in comparison to the yield obtained in control. The uptake of S at maturity was significantly affected with all the levels of S application. The seed S uptake increased significantly up to 30 kg S ha^?1 and stover 45 kg S ha^?1. The residual effect of S was convincing in enhancing the rice yield to the tune of 5.3% over control, but was statistically non-significant. The S uptake was also favourably influenced by the residual S which was evidenced through increased S use efficiency. Agronomic and physiological efficiency as well as S recovery were all greatly influenced by direct and residual effect of S. Apparent S recovery was higher at 30 kg S ha^?1 in mustard (12.06%).     

Comparing the Nitrogen and Potassium Requirements of Canola and Wheat for Yield and Grain Quality

ABSTRACT

Grain yield increases (responses) of canola (oilseed rape, Brassica napus L.) and spring wheat (Triticum aestivum L.) to application of nitrogen (N) and potassium (K) fertilizers were compared in the same experiment at eight field sites over three years (2000–2002) in southwestern Australia. Four rates of N (0–138 kg N/ha as urea) and four rates of K (0–60 kg K ha^?1 as potassium chloride) were applied. Significant grain yield responses to applied N and K occurred for both crop species at all sites of the experiment, and the NxK interaction was significant. Canola required an average of 26% more applied N and 32% more applied K than wheat to produce 90% of the maximum grain yield. Applying increasing rates of K increased the rate of N required for 90% of maximum grain yield. Likewise, applying increasing rates of N increased the rate of K required for 90% of the maximum grain yield. Fertilizer K had no significant affect on the concentration of oil in canola grain or concentration of protein in both canola and wheat grain. Application of increasing rates of N decreased the concentration of oil while increasing the concentration of protein in canola grain, and increased concentration of protein in wheat grain. The NxK interaction was not significant for concentration of oil or protein in grain.     

Boron nutrition for improving the quality of diverse canola cultivars

Abstract

Canola (Brassica napus L.), is the most important oilseed crop due to high oil contents and low concentration of erucic acid and glucosinolates. In Pakistan, oil seed production is not sufficient to fulfill the needs of the country. Thus, the planned experiment was aimed to evaluate the performance of different canola cultivars i.e. Faisal Canola, Pakola, PARC Canola hybrid and Rainbow at grown under various soil applied boron (B) levels viz., 0, 1, 2?kg ha^?1 under a rainfed environment. The experiment was laid out in randomized complete block design with four replications. Among the canola cultivars, the maximum seed oil contents were recorded in cultivar ‘Pakola’ whereas, higher linolenic acid and protein were recorded in cultivar ‘Faisal canola’ as compared to other cultivars. A synergistic effect was found between various levels of B and quality parameters of the canola seed; as higher concentration of oil contents were found when B was applied 2?kg ha^?1. Conversely the linolenic acid showed the antagonistic behavior with the various B levels. On the other hand, protein contents, oleic acid and erucic acid revealed non-significant differences under different B application rates. In conclusion, the cultivar ‘Pakola’ provided the highest oil content when the B was applied at 2?kg ha^?1; the low concentration of unsaturated fatty acid was observed in ‘PARC canola’ cultivar in the Pothwar region of Punjab, Pakistan.     

Cumulative Effect of Soil and Foliar Application of Nitrogen,Phosphorus, and Sulfur on Growth,Physico-Biochemical Parameters,Yield Attributes,and Fatty Acid Composition in Oil of Erucic Acid-Free Rapeseed-Mustard Genotypes

ABSTRACT

The feasibility of split (soil + foliar) applications of nitrogen (N) and phosphorus (P) and addition of a small quantity of sulfur (S) in the spray was tested for improving performance of rapeseed-mustard genotypes in a factorial randomized field experiment. Three genotypes (two erucic acid free, viz. Brassica napus L. cv. ‘Hyola PAC – 401’ and Brassica juncea L. Czern. and Coss. cv. ‘TERI (0E) M 21-Swarna’, and one best performing high yielding Brassica juncea L. cv. ‘Rohini’ as a check) were grown with four soil (B) plus foliar (F) applications of N, P, and S with uniform basal 30 kg potassium (K) ha^{? 1} (K₃₀), viz. (i) the optimum soil-applied treatment supplemented with the spray of deionized water (B_N90P30 + Fw) comprising control, (ii) B_N70P30 + F _N20, (iii) B_N70P28 + F_N20P2, and (iv) B_N70P28 + F_N20P2S2. Soil Plus foliar application of nutrients, particularly B_N70P28 + F_N20P2S2, improved their performance with respect to growth characteristics (shoot length plant^{? 1}, leaf number plant^{? 1}, area leaf^{? 1}, leaf area index, fresh weight plant^{? 1}, and dry weight plant^{? 1}), physico-biochemical parameters (net photosynthetic rate, stomatal conductance, carboxylation efficiency, water use efficiency, carbonic anhydrase activity, leaf NPK content, and N use efficiency), yield attributes (pod number plant^{? 1}, seed number pod^{? 1}, 1000-seed weight, seed yield ha^{? 1}, oil content, and oil yield ha^{? 1}), and fatty acid composition in oil of these genotypes. The cultivar ‘Hyola PAC-401’ performed best particularly with B_N70P28 + F_N20P2S2. The improvement in the response of genotypes to the split application of nutrients may be attributed to their ready availability through foliar application.     

Growth,Yield and Quality Components of Canola Fertilized with Urea and Zeolite

In the present study, integration of nitrogen (N) and zeolite on growth, photosynthesis, yield and yield components, nitrate reductase activity, and plant nutrient content on canola (Brassica napus L. cv. SLM₀₄₆) was evaluated during two growing seasons (2010 and 2011) at East Azerbaijan Research Center for Agriculture and Natural Resources, Tabriz, Iran. The experiment was conducted as a 4?×?5 factorial design with three replications. Different levels of zeolite (0, 4, 8, and 12 ton ha^?1) and nitrogen (N; 0, 150, 200, 250, and 300 kg ha^?1) were added and mixed with soil thoroughly. According to combined analysis of variance, effect of year was significant only on silique number per plant, respiration rate, and iron (Fe) content. Also results indicated that N fertilizer increased plant height, silique number per plant, seed number per silique, 1000-seed weight, and finally seed yield. Similarly, zeolite increased yield and yield components whereas plant height was not affected by zeolite in the second year. Oil yield decreased due to N and zeolite application. In addition, photosynthesis and respiration improved on account of N and zeolite treatments. Nitrate reductase activity significantly was promoted by N and zeolite. Furthermore, micro- and macroelements were affected by N or zeolite application, so that N and zeolite decreased P content whereas N increased N, K, Fe, and zinc. In general our results demonstrated that zeolite application can increase canola growth and production, which may be through increasing N-use efficiency and improving soil physical characteristics.     

EFFECTIVENESS OF SEEDROW-PLACED N WITH POLYMER-COATED AND NBPT-TREATED UREA FOR CANOLA AND WHEAT

Seedrow-placed urea minimizes soil disturbance in reduced tillage systems, but it generally decreases seedling emergence (or stand density) at nitrogen (N) rates adequate for optimum crop yield. Two three-year field experiments were conducted on canola (Brassica napus L.) and spring wheat (Triticum turgidum L.) at Melfort Research Farm, Saskatchewan, Canada, to determine the influence of N rate (40, 80 and 120 kg N ha^?1), N source [untreated urea (urea), polymer-coated urea (ESN), and urea treated with Dicyandiamide (DCD) and N-(n-butyl) thiophosphoric triamide (NBPT or Agrotain^TM) (SuperU) in 2007, or NBPT only (AgrotainU) in 2008 and 2009], and placement (side-banded N and seedrow-placed N, using knives to create 2 cm wide band), plus a zero-N control, on seedling emergence, seed and straw yield, protein concentration (PC) in seed, and N uptake in seed and straw. For both crops, side-banded N had no detrimental effect on seedling emergence compared to the zero-N control for all rates and sources. Seedrow-placed ESN had little or no effect on seedling emergence of wheat or canola. Conversely, seedrow-placed urea, SuperU or AgrotainU reduced seedling emergence for wheat at the 80 and 120 kg N ha^?1 rates and reduced canola seedling emergence substantially at all rates, but particularly at the 80 and 120 kg N ha^?1. Seed yield and N uptake were generally greater with ESN than urea and also SuperU or AgrotainU, when the fertilizers were seedrow-placed at high N rates. The findings suggest the effectiveness of ESN in providing greater seedrow-placed N application options for producers.     

Effects of Sulfur and Water Supply on Quantitative and Qualitative Traits of Indian Mustard

Oilseed production can be affected in arid and semi-arid regions that are exposed to water shortages. Nevertheless, cultivation of drought-resistant crops such as Indian mustard is a suitable way to gain acceptable yields. Effects of different levels of irrigation and sulfur (S) fertilizer on the quantity and quality parameters of mustard (Brassica juncea) were assessed in a trial at the Indian Agricultural Research Institute, New Delhi, during 2007–2008 and 2008–2009 growing seasons. The experiment was carried out in a split plot as randomized complete block design with three replications. The experiment treatments consisted of three irrigation levels [no irrigation, one irrigation at 45 days after sowing (DAS), and two irrigations at 45 DAS and 90 DAS] in main plots and four sulfur levels (S; 0, 15, 30, and 45 kg S ha^?1) in subplots. The results showed that in the two successive years of the experiment, the number of siliquae/plant, length of siliqua, number of seeds/siliqua, and 1000-seed weight increased significantly with increasing the level of irrigation, which resulted in greater seed yield than no irrigation. Also, mustard plants irrigated two times showed the greatest values of nitrogen (N), protein, and oil content of the seeds over no irrigation in both years of this study. The oil yield and S content in the seed of mustard increased significantly with increasing the level of irrigation in both years. Number of siliquae/plant, siliqua length, number of seed/siliqua, and 1000-seed weight increased significantly with increasing the rates of S up to 45 kg S ha^?1 in both years of experimentation; however, in 2008–2009 the difference between application of 30 and 45 kg ha^?1 S was not statically significant. Also, the seed yield, N, protein, oil, and S contents in seeds of mustard increased significantly with increase in the level of applied S in both years.     

EFFICACY OF GYPSUM AND MAGNESIUM SULFATE AS SOURCES OF SULFUR TO RAPESEED IN LATERITIC SOILS

A field experiment conducted on rapeseed (Brassica juncea L.) during 2005–2006 in a typical lateritic soil (Alfisol) of West Bengal, India revealed that sources of sulfur viz. gypsum and magnesium sulfate and levels of sulfur (0, 20, 40, 60 kg S ha^?1) have significant influence on grain yield, total biological yield, sulfur concentration in grain and stover, total sulfur uptake, oil content and oil yield and chlorophyll content. The maximum grain yield (18.28 q ha^?1) and oil yield (8.59 q ha^?1) was obtained with magnesium sulfate followed by gypsum yielded the grain yield of 17.99 q ha^?1 and oil yield of 8.22 q ha^?1 at 40 kg S ha^?1. Overall, the best performance was recorded when sulfur was applied at 40 kg S ha^?1 either as magnesium sulfate or gypsum. Results revealed that magnesium sulfate may be considered as the better source of sulfur than gypsum to raise the mustard crop in sulfur deficient acidic red and lateritic soils of West Bengal and if farmers apply either magnesium sulfate or gypsum to soils, the possible deficiency of sulfur and magnesium/calcium in soils and plants can be avoided.     

RESPONSE OF ALFALFA SEED YIELD AND YIELD COMPONENTS TO PHOSPHORUS FERTILIZING SYSTEMS AND SEEDING RATE AT SEMI-SALINE SOIL CONDITIONS

To study the effects of phosphorus (P) fertilizer (cow manure, phosphorus solublizing bacteria) and sowing density on seed production of alfalfa, an experiment was laid out in a three-replicated split-split plot design with four phosphorus fertilizer rates (0, 30, 60 and 90 kg ha^?1) in main plots, three phosphorus-solublizing bacteria (9, 41strains, and no bacteria) in sub-plots and three sowing densities (2, 6 and 10 kg ha^?1) in sub-sub plots. The highest seed yield resulted from 60 and 90 kg P ha^?1. Application of bacteria strain 41 was more efficient than bacteria strain 9 in seed yield and 1000-seed weight. Seed yield at 6 seed kg ha^?1 treatment was higher than 10 kg ha^?1, although there was no significant difference between them. Based on the results of this experiment the triple application of P60, B41 and SD6 could be recommended as the best treatment for seed production of alfalfa (Cultivar ‘Nikshahri’) under the semi-saline condition.     

Yield,yield formation,and blackleg disease of oilseed rape cultivated in high-intensity crop rotations

The short-term economic benefit has in recent years prompted farmers to grow oilseed rape (OSR) (Brassica napus L.) and thus the frequency of this crop increased in German crop rotations. Here, we investigate the impact of high-intensity OSR crop rotations on yield, yield formation, and blackleg disease (Leptosphaeria maculans) in a rotation experiment in the Hercynian dry region of Central Germany over two seasons (2014/2015?–?2015/2016). The preceding crop combinations compared were winter wheat (WW) (Triticum aestivum L.)-WW, WW-OSR, OSR-OSR, and an OSR monoculture. Furthermore, the fertilizer treatments 120 kg N ha^?1 and 180 kg N ha^?1 were analyzed.

Higher OSR cropping intensity decreased seed yields, however, with a variation among years and oil yield was highest when OSR was following WW-WW over both years. Minor differences were observed among the yield components, but significantly less pods per m² were developed in a long-term OSR monoculture. The disease assessment clearly showed an increased blackleg incidence and severity when OSR was grown successively.

Results of our study emphasize that high-intensity OSR production will very likely be unsustainable over the long term associated with yield losses and increased infestation levels of blackleg disease.     

Optimizing the NPK application in white mustard (Sinapis alba L.) under an arid climate in Punjab,Pakistan

The production of oil from the conventional oilseed seed crops (viz. mustard, rapeseed) is not sufficient to meet the demands of Pakistani people. Due to this reason, a surplus quantity of oil is imported every year from different countries to fulfill the domestic demands of the cooking oil. This 2-year study was aimed to optimize the dose of NPK for profitable production of white mustard. Nitrogen (0, 60, 90?kg ha^?1), phosphorous (0, 30, 60?kg ha^?1) and potassium (0, 75, 100?kg ha^?1) were applied in various combinations. The results indicated that highest seed yield and profitability was recorded with NPK at 90–60–100?kg ha^?1, which was attributed to improvement in crop growth. In crux, application of NPK at pre-optimized rate might be a viable option to improve the growth, yield, oil quality, and economics of white mustard production under arid climates in Pakistan. According to the results, a balanced use of NPK fertilization is a key management strategy for white mustard growing farmers of arid region.