Beryllium effects on potatoes and oats in acid soil

The most likely means of Be entry into the food chain would appear to be via root, tuber, and forage crops grown on acid soils. Potatoes (Solanum tuberosum) and oats (Avena sativa) were grown in greenhouse pots of a strongly acid soil treated with 0 to 300 ppm Be and 0 to 1000 ppm CaC0₃. Germination and yield decreased, and plant Be content increased, with increasing soil Be content. The Be content of the potato tubers appeared to be low and unaffected by the soil Be content. Liming the soil and increasing the time between Be contamination and crop planting lessened the effect of Be.     

Influence of tuber weight and cutting on growth and yield of safed musli (Chlorophytum borivilianum)

The present study was aimed to investigate the effect of different weight of planting material and cutting on safed musli cultivation. Tubers were divided into three weight categories (3, 6 and 9 g bulk^?1) and were either planted as whole or cut tubers. The plant growth and development were recorded at 60, 90 and 120 days after sprouting (DAS). The results showed that both factors had no interaction for all parameters measured. The sprouting percentage was not significantly different in all the treatments. The weight of planting materials used in the treatments had no influence on the overall plant growth and development. However, there was a significant difference observed between whole tuber and cut tuber treatments. At 90 DAS, tubers subjected to cutting encouraged the plants to produce the higher number of leaves (22.7) with improved total leaf area (642 cm²), fibrous root length (2795 cm) and tuber dry weight (7.8 g). The same pattern was observed at 120 DAS where the cut tubers produced the higher number of tubers (20.7) with increased length (8.6 cm) and diameter (6.6 mm). Consequently, these factors resulted in higher yield, 15.7 as compared to 13.6 g bulk^?1 in non-cut treatment.     

Irrigation and Nitrogen Fertilizer Rate Impacts on Soil Nitrate in Potato Production

ABSTRACT

Parts of the Kern County have high nitrate levels in groundwater. A State Water Resources Control Board commissioned report has indicated that crop land agriculture is the main source of nitrates in the groundwater. Annual rainfall is less than 20 cm, thus irrigation is necessary for optimum crop production. A project was undertaken to evaluate current nitrogen fertility and irrigation scheduling in potato production and their contribution, or lack thereof, to nitrate movement in the soil profile and potential nitrate contamination of groundwater. A line-source sprinkler plot area was established to create soil moisture regimes of 120% of target, target (optimum soil moisture for potato growth) and 80% of target. Pre-plant and post-harvest soil samples were collected to a depth of 2 meters. Plant, root and tuber samples were collected and analyzed for nitrogen content. Soil moisture and irrigation amounts were monitored. Plant dry matter and tuber yield increased with each N rate increase. The high N rate increased plant growth disproportionally to the increased tuber yield. Appropriate irrigation scheduling did not produce water movement beyond the effective potato rooting zone. Excessive irrigation moved soil nitrate deeper into the soil profile.     

Effects of mouldboard ploughing and direct planting on yield and nutrient uptake of potatoes in Norway

The use of conservation tillage systems is now widespread for cereals in erosion-prone areas of Norway. However, few growers are willing to adopt such practices for other crops. An experiment was conducted in southern Norway (60°46′N, 10°49′E) from 1987 to 1993 to compare the effects of two different tillage treatments on potato (Solanum tuberosum L.) yield and quality. The conventional labour-intensive treatment, with autumn mouldboard ploughing, levelling and two passes with a spring-tine harrow in spring was compared with planting directly into untilled barley (Hordeum vulgare L.) stubble, with straw removed. The soil type in the experiment was a morainic, stony loam (Typic Cryoboroll, Orthic Melanic Brunisol). Prior to the start of the experiment direct-planted plots had not been ploughed for 9 years. During the trial years (1987–1993) a pattern of two different yield curves emerged as functions of the date of harvesting. The yield curve for direct planting was steeper, crossing that of conventional tillage on approximately 10 September, thus predicting higher tuber yield for direct planting when harvesting occurred after this date, but lower tuber yield than with conventional tillage in the case of early harvesting. The reason for this is thought to be cooler soil and delayed growth and maturation with direct planting. Furthermore, direct planted potatoes gave higher haulm yield, and also had higher contents of N, P and K in both haulm and tubers. No significant differences in tuber quality were found between the two treatments. A strong negative correlation was found between the yield increase caused by direct planting and mean air temperature in August. The trial indicated that direct planting of potatoes in cereal stubble is a viable alternative to conventional plough tillage on loam soil in Norway, provided that the growing season is adequately long.     

Effect of time of mulching on soil temperature and moisture regime and emergence, growth and yield of white yam in western Nigeria

Time of mulching can influence the growth environment and performance of white yam (Dioscorea rotundata Poir). An on-farm trial was conducted during the 1988–1989 and 1989–1990 seasons (October–August) in Nigeria to determine the effect of time of mulching (October–February) on the hydrothermal regime and emergence, growth and tuber yield of white yam. Application of 12.5 mg ha⁻¹ of dry Eupatorium odoratum L. (Syn. Chromolaena odorata L.) mulch on top of the mounds significantly improved soil moisture content of the 15 cm surface layer by 50–120 g kg⁻¹ and decreased the maximum soil temperature by 2–7°C at 15 cm depth in the early growing season (March–April). The emergence and development of yam seedlings were significantly lower in unmulched plots than in mulch-treated plots. Mulching significantly increased tuber yield by about 10–15 mg ha⁻¹ season⁻¹. Plots mulched in October–December were more moist by 20–60 g kg⁻¹ and cooler by 1–3°C, and had 27–44% greater emergence than those mulched in January or February. The number of leaves per plant, vine diameter and leaf area index were also significantly greater in plots mulched in October–December than plots mulched in January or February. Consequently, shoot dry weight was about 28–36% greater in yam mulched in October–December than in yam mulched in February. However, the time of mulching had no effect on soil moisture of the surface layer at the beginning of the rainy season (April), on yam emergence in May and on tuber yield and yield components. Although time of mulching did not significantly affect tuber yield, the increase (10–15%) in the tuber yield of yam mulched in December–February compared to the yam mulched in October or November was considerable. It was concluded that yam planted in October, just before the rain stops, can be mulched in January or February without detrimental effect on emergence, growth and tuber yield.     

Effects of no-till and disc plowing with and without residue mulch on tropical root crops in southeastern Nigeria

Fields experiments were conducted on an Ultisol in southeastern Nigeria to study the effects of no-tillage and disc plowing, with and without residue mulching, on soil properties and the growth and yield of cassava and yam. Plowing to a depth of 10 cm and then applying mulch decreased soil bulk density. Of the no-till plots, those with mulch had the greatest soil moisture retention at low suctions; those without mulch had low moisture retention for suctions exceeding 0.1 bar. Cassava plants in plowed plots were more vigorous than those in no-till plots, and mulching decreased plant height of cassava in the initial stages and increased plant height at about 38 weeks after planting. In the first 10 cm, yam root length density was 0.31 cm cm⁻³ for no-till plots vs. 0.27 cm cm⁻³ for plowed plots. Mulch application increased root length density of yam. The root length density of cassava was 0.32 cm cm⁻³ for no-till plots versus 0.16 cm cm⁻³ for plowed plots. Mulch application, however, significantly increased root length density of cassava in no-till plots only. Yield of yam tubers was more for plowed plots than no-till plots — 12.4 vs. 10.9 t ha⁻¹. The increase in yam tuber yield due to mulching was 21% for no-till and 28% for plowed treatments. The cassava tuber yield was more in no-till than in plowed plots, and application of mulch increased cassava tuber yield.     

Potato uptake and recovery of nitrogen 15N-enriched ammonium nitrate

Tuber yield and nitrogen uptake in potatoes were recorded during 1996 and 1997 in Southern Bavaria. Recovery of applied fertilizer nitrogen was measured by using ¹⁵N (¹⁵NH₄¹⁵NO₃). Nitrogen fertilizer was brought out either broadcast or in the ridge; 150 kg N ha⁻¹ were applied either at planting or in split doses of 50 kg N ha⁻¹ (at planting, emergence and at 20-cm plant height). Due to unfavorable conditions, tuber yield and fertilizer N recovery were lower in 1996 as compared with 1997. Fertilizer N recovery in plant biomass (tuber and foliage) ranged from 35.9% to 68.5% at growth stage EC 79; the main fraction was allocated to tubers. Placement of fertilizer N in the ridge had a positive effect on N recovery, when the total N amount was applied at planting. In broadcast application, fertilizer N recovery was higher when the fertilizer doses were split, as compared with a single broadcast application at planting. When fertilizer N was applied in split doses, the effect of N placement became negligibly small. Fertilizer N recovery in soil ranged from 19.5% to 24.6%, and total recovery ranged from 60.1% to 88.0%. Rainfall between planting and plant emergence, and conditions restricting plant development in early developmental stages were related with unaccounted fertilizer N losses. Therefore, the positive effects of split N applications or fertilizer placement are most likely to occur under unfavorable growing conditions.     

Phosphorus compounds and their solubility in swine manure compost

In the Japanese warm areas, as a result of intensive and repeated potato cropping, common scab, a soil-borne disease has become a serious problem. The soil moisture level has been shown to be an important factor affecting the incidence of common scab. That is, a high level of soil moisture reduces the severity of common scab. However, in this investigation, although during the spring cropping precipitation was abundant, a large number of tubers showing scab lesions were produced. The results indicate that the soil moisture level may not be an important factor affecting the incidence of potato scab in the humid region.

To identify other factors which may affect scab severity, the relation between sugar content in the peel of potato tuber and the incidence of common scab was investigated. Generally, the amount of reducing sugar in the tuber peel increased gradually with the growth of the tubers, then reached a maximum level two weeks after the start of tuber formation, and thereafter declined. The period corresponding to the highest sugar content in peels coincided with the most susceptible period for scab infection. The content of reducing sugar in the peel of susceptible cultivars was higher than that of the resistant cultivars, throughout the tuber growth, and the critical value of the content was 2.0 mg per 100 g fresh peel. These results suggest that the content of reducing sugar in tuber peel may be an important factor affecting the incidence of common scab.     

Effects of late planting on fiber quality and within-boll yield components as mediated by sucrose metabolism in cotton bolls

ABSTRACT

The objective of this study was to examine the effect of late planting on sucrose metabolism in cotton bolls and the relationship to fiber properties and within-boll yield components. Two cotton lines A201 and A705 were employed in a sowing date experiment where two temperature regimes during boll maturation period were created at mean daily temperature of 26.8°C, 28.3°C for early planting and 25.2°C, 23.1°C for late planting in 2016 and 2017, respectively. Boll size, seed mass per boll, seed index and fiber length were increased, and lint percentage was decreased by late planting. Greater cell wall invertase activity and the resultant hexose concentration in fibers were observed in late planting, and thus led to decreased osmotic potential accounting for the enhanced fiber length. Similarly, late planting increased the maximum of vacuolar invertase activity in ovules occurring at 5 days post anthesis (DPA) and hexose concentrations in embryos from 10 DPA afterwards which may favor embryo cell division, and thus increase final seed size. Our data indicate that acid invertase and hexose are implicated in the formation of within-boll yield components and fiber properties as affected by the lower temperature regime due to late planting.     

Different pre-sprouting methods for early tuber harvest in potato (Solanum tuberosum L.)

Abstract

Earlier harvest of potatoes (Solanum tuberosum L.) can be achieved by different treatments of the seed tubers. This can be important, for example, in areas with a short growing season and in organic farming. In a pot experiment, different pre-sprouting methods were evaluated for four cultivars. The experiment consisted of (a) untreated seed tubers stored at 4 °C until planting, (b) traditional pre-sprouted tubers (P) and (c) pre-sprouted tubers with stimulation of adventitious root formation (PR). Pre-sprouted seed tubers have earlier and faster tuber formation, but often lower yield than non pre-sprouted tubers if there is no restriction of the growing season. The PR method developed here, where tubers were sprayed with water to stimulate adventitious root formation and give faster development and tuber initiation than conventional pre-sprouting, can be of value when the growing season is restricted or if early harvest is important. Initial emergence of the pre-sprouted potatoes was monitored in two pot experiments. Emergence was faster for the pre-sprouted treatments compared with the control, but there were no significant differences between the two pre-sprouting methods. At harvest, the pre-sprouted treatments gave higher yield than the control for all growing periods, methods and cultivars, although the differences were not significant for every combination. The cultivars Matilda, Cicero, Ovatio and Superb seemed to respond more positively in terms of yield to PR treatments than cv. Ditta. The new method for stimulating adventitious root formation developed here will substantially help growers to achieve earlier harvests.     

Bio-Efficacy of Microbial Infused Rice Straw Compost on Plant Growth Promotion and Induction of Disease Resistance in Chili

ABSTRACT

Microbial fortified organic amendment in chili cultivation may affect plant development and disease suppression. Microbial infused rice straw compost, commercial rice straw compost, and fungicide Benomyl for chili (Capsicum annum L.) cultivation and control of Sclerotium foot rot were studied under glass house condition. Chili seed cv. Kulai were sown in the Sclerotium rolfsii infested and non-infested soil. After two weeks, five healthy seedlings were transplanted into planting bags. Growth performance and development of disease symptoms associated with S. rolfsii foot rot infection were assessed. Applying microbial infused rice straw compost increased seed germination and plant growth, and suppressed development of foot rot compared to using commercial rice straw compost and the Benomyl. A higher disease reduction (84.6%) occurred with 15 Mg · ha^?1 microbial infused rice straw compost (62.7%), followed by Benomyl (53.8%), and 15 Mg · ha^?1 commercial rice straw compost (46.2%). Application of microbial infused rice straw compost at 15 Mg · ha^?1 yielded optimum seed germination and seedling establishment, plant growth, and disease suppression. Microbial infused rice straw compost is a good alternative to chemical fungicide in controlling Sclerotial disease in chili.     

The Effect of Humic Substances and Phosphate Fertilizer on Growth and Nutrient Uptake of the Potato

ABSTRACT

The use of applied phosphorus (P) and the uptake of nutrients from the soil by plants can be improved when the fertilizer is combined with the application of humic substances (HS). However, these beneficial effects are inconsistent and can depend on the type of soil. This study was performed to evaluate the effects of the application of HS (0, 1.25, and 7.50 mL pot^–1), as Humic HF®, and fertilizer-P (10, 50, 100, and 200 mg P dm^–3), as triple superphosphate, on root morphological characteristics, dry matter accumulation, nutrient uptake, and tuber yield of potatoes grown in sandy and clayey soils. Only under low P supply in the sandy soil did the supply of HS, at the rate of 1.25 mL pot^–1, increase the plant growth, yield of tubers, and uptake of macronutrients by the plants, without affecting the efficiency of the P fertilization. In the clayey soil, which had a higher organic matter content, the application of HS did not affect plant growth, tuber yield or nutrient uptake. In both soils, P fertilization increased plant growth, tuber yield, and nutrient uptake. The combined application of HS and P increased the root length of potatoes in sandy soil.     

Boron fertilization effects in processing grade potato on an Inceptisol of West Bengal,India

A 2-year field trial was conducted in processing grade potato cv. Kufri Chipsona-3. The treatments comprised recommended dose of fertilizer (RDF) (200:150:150 N:P₂O₅:K₂O kg ha^?1) with or without boron (B) application (soil and foliar). The results revealed that B fertilization significantly increased tuber number and yield. Three sprays of 0.1% boric acid (at 40, 50 and 60 days after planting) produced the maximum number and yield of tubers and enhanced B uptake in potato tuber, haulm as well as in total plant accounting 85.8, 182.0 and 169.8% more than control, respectively. The same treatment came up with greatest net return and benefit: cost ratio. B fertilization exerted significant influence on available N and B status of post-harvest soil, while the effect was non-significant on available P and K. Results suggest that right dose and method of B application is vital for optimizing tuber yield and B-use efficiency for processing grade potato.     

Seasonal variation and low-cost agronomic practices effect growth and yield of moth bean (Vigna aconitifolia) in the extreme arid Thar desert

An experiment was laid out at Jaisalmer for three consecutive rainy seasons (2007 to 2009) to evaluate the effect of season and the efficacy of low-cost agronomic practices on the performance of moth bean (Vigna aconitifolia L.) in the extreme arid Indian Thar. Skip row planting (skipping every third row) significantly improved pods and seed weight per plant, and consequently seed yield, over normal planting. Total readily available water and moisture availability at critical growth stages of the crop significantly influenced plant attributes and thus biological and seed yield. Relative leaf water content (RWC) at sunrise in the pre- and post-flowering stages remained above the moisture stress level. However, at midday, plants experienced moderate stress in RWC during pre-flowering and severe stress during the post-flowering stages. Foliar application of 1% urea was found to be effective only when midday RWC is more than the critical threshold value of 84%. Therefore, foliar application of 1% urea at the pre-flowering stage significantly increased almost all plant attributes and yields, whereas second foliar application at post-flowering stage when midday RWC was <84% has no impact on plant attributes and yield.     

Tuber yield and allocation of nutrients and carbohydrates in potato plants as affected by limestone type and magnesium supply

Abstract

Magnesium (Mg) is a nutrient that affects the development of plants and is mainly supplied through liming performed to correct soil acidity. By acting on photosynthesis and influencing carbohydrate partitioning in the plant, supplementary Mg supplied through soil or foliar application can increase the yield and quality of potato (Solanum tuberosum L.) tubers. The aim of this study was to evaluate the effect of supplemental Mg fertilization by soil or foliar application on plant nutritional status, tuber yield, and carbohydrate partitioning in potato crops in soil corrected with calcitic and dolomitic limestones. The experiment was carried out in pots under greenhouse conditions with a randomized block design in a 2?×?3 factorial scheme with four replications. Dolomitic limestone application and supplemental Mg fertilization via soil increased the concentrations of this nutrient in potato leaves. Liming with dolomitic limestone reduced the uptake of Ca and K by plants, but supplemental Mg fertilization did not alter the uptake of Ca, Mg or K. Supplemental Mg fertilization did not increase plant growth and tuber yield, even when calcitic limestone was used to elevate the base saturation to 60%; the exchangeable Mg concentration in soil was 9?mmol_c dm^?3, and the Ca:Mg relationship was 3.7. Liming with dolomitic limestone or providing supplemental Mg fertilization did not increase sugar and starch partitioning to the tubers.     

Nitrogen balance of nitrogen-15 applied as ammonium sulphate to irrigated potatoes in sandy textured soils

Farmers are applying very high amounts of N fertilizer (sometimes >900 kg N/ha), commonly (NH₄)₂SO₄, to irrigated potato (Solanum tuberosum, L.) grown on sandy textured soils in the Cappadocia region of Turkey. To obtain information on potato yield, N uptake, N fertilizer residue in the soil and the portion of N fertilizer leached below 200 cm soil depth, nine field experiments were conducted at three different locations in 1992, 1993 and 1994. The N rates used in these experiments were 0, 200, 400, 600, 800 and 1,000 kg N/ha within a completely randomized block design with three replicates. N fertilizer was applied in two equal portions; one at planting and one just before the first irrigation. Although all yield data were used to find out the marketable tuber yield, the N rate response curve and the fate of applied fertilizer N was determined only for the 400 and 1,000 kg N/ha rates. Isotope microplots were established where ¹⁵N-labelled (NH₄)₂SO₄ was applied at 5.0 atom % and 2.5 atom % excess enrichments for the 400 kg N/ha and 1,000 kg N/ha rates, respectively. At harvest, marketable and dry tuber yield was determined for all N rates. Dry tuber and leaf plus vine yields were determined for the isotope microplots and they were analysed for the % N and ¹⁵N atom % excess. The % N derived from fertilizer and N use efficiency (%NUE) were calculated for the plant samples. The ¹⁵N-labelled residue left in 0-200 cm soil was also determined. The amount of N fertilizer leached below 200 cm soil depth was also calculated. ¹⁵N-labelled NO₃^- and total NO₃^- of the groundwater from wells were determined at different dates. Our results show that the optimum marketable tuber yield was obtained with 600 kg N/ha. Tuber N uptake was increased slightly, while leaf plus vine N uptake increased considerably when the N rate was increased from 400 to 1,000 kg N/ha. The %NUE values decreased nearly by half and the amount of N fertilizer in the 0-200 cm soil layer increased more than 3 times when the N rate was increased from 400 to 1,000 kg N/ha. Nearly half of the applied fertilizer N (45.6%) at 400 kg N/ha and more than half of the applied fertilizer N (60.8%) at 1,000 kg N/ha was still in the 0-200 cm soil layer after harvest. Four times more N fertilizer was leached below 200 cm soil depth when 1,000 kg N/ha N was applied instead of 400 kg N/ha. Our results also indicate that there is a potential contamination of groundwater due to leaching of the applied N fertilizer.     

宽垄沟播种植模式对夏玉米生长发育及水分利用率的影响

探讨水地条件下种植模式对夏玉米产量及水分利用的影响,为夏玉米节水种植高产稳产栽培提供依据。以玉米品种"登海685"为试验材料,研究宽垄沟播和等行距平播模式下不同种植密度(6.00,6.75,7.50万株/hm~2)对夏玉米生长发育、产量、养分吸收及水分利用率的影响。结果表明:沟播种植模式较平播增加玉米植株株高,使茎粗和单株干物质重降低。沟播模式的穗性状比平播处理较优,单穗重增加,且受种植密度影响较小,表现出明显的边行优势。沟播模式的玉米叶片叶绿素相对含量始终高于平播处理,生育期延长,为后期籽粒形成提供了物质保障。在种植密度为7.50万株/hm~2时,沟播模式夏玉米产量最高。沟播模式下夏玉米灌水量较平播减少52.9%,灌水时间减少50.1%,日均蒸发量减少,且水分含量高于平播处理,使灌溉水利用效率提高139.5%,水分利用效率平均提高16.7%。可见,宽垄沟播是夏玉米增产增效的一种节水种植模式,明显提高玉米水分利用效率。     

模拟降雨量条件下沟垄集雨种植对土壤养分分布及夏玉米根系生长的影响

为了探索沟垄集雨种植的增产机理及其适宜的雨量范围,在人工模拟降雨条件下研究了不同降雨量沟垄集雨种植对夏玉米（ZeaMaysL．）根系性状及土壤速效养分含量的影响。结果表明,沟垄集雨种植处理后,耕层（0~40cm）土壤速效N、P、K和有机质的含量明显增加（P〈0．05）。夏玉米根长、根表面积、根体积和根干重在230mm和340mm降雨量下明显增加,440mm雨量下,分别有所减小（P〈0．05）;籽粒产量增加幅度在230~440mm雨量下随雨量增大而减小（P〈0．05）,440mm时增产效果已不明显。可见,沟垄集雨种植协调了土壤水分和养分的关系,在一定雨量下可促进植株根系的发育,其种植玉米适宜的雨量上限可能在全生育期降雨量440mm左右。     

Development of field-grown potato plants derived from meristem plants multiplied with different methods

Abstract

In the current multiplication technique first-generation seed tubers produced in the field by transplanting plants raised on peat in plastic rolls from plants cultured by repetitive multiplication using tip- and stem-cuttings and truncated plants are compared with in vitro micro-plants from the aspect of obtaining optimal-sized, disease-free seed tubers.

The objective of the study is to compare the dynamics of total plant dry mass and tuber dry mass of field-grown potato plants, and analyse the effect of the year and variety. Two local late-maturing potato varieties, Ants and Vigri, were used in the study. The field experiments were carried out in 2005–2007.

Significant impact of the multiplication method and experimental year on total plant dry mass and tuber dry mass was observed. The plants multiplied in vitro from micro-cuttings produced lower total dry mass and also lower tuber dry mass per m². The plants multiplied by tip- and stem-cuttings as well as truncated plants proved to be more adaptable to unfavourable weather conditions than in vitro plants; in a favourable year, however, the differences were insignificant. In the early phase of growth the ratio of the tuber dry mass to total plant dry mass increased more rapidly in the case of in vitro plants, whereas by the end of the growing season the relevant ratio was similar for all multiplication methods and years.

All developed multiplication methods are suitable for practical seed potato production in the field and ensure a reasonable potato crop.