茄子/大葱间作及氮肥调控对植株硝酸盐含量及养分吸收的影响

作物根系分布深度不同,其吸收养分的土壤区域也有所不同。采用大田试验方法,选择深根系的茄子和浅根系的大葱进行间作种植,并辅以氮素调控措施,研究其对蔬菜硝酸盐含量及养分吸收的影响。研究表明,无论是常规施肥还是减量施肥,间作均能降低蔬菜体内硝酸盐含量。间作区茄子的生物量和吸氮、磷、钾量均高于单作区,而间作区大葱的生物量及吸氮、磷、钾量均有所降低。说明在这一间作模式中,茄子处于优势地位,而大葱处于劣势地位。     

Interactive Effect of Sulfur and Nitrogen on Nitrogen Accumulation and Harvest in Oilseed Crops Differing in Nitrogen Assimilation Potential

ABSTRACT

Field experiments were conducted to determine the interactive effect of sulfur (S) and nitrogen (N) on nitrogen accumulation, its distribution in various plant parts, and nitrogen harvest of oilseed crops viz. rapeseed (Brassica campestris L. cv. ‘Pusa Gold’) and taramira (Eruca sativa Mill.) differing in their N-assimilation potential. Two combinations of S and N (in Kg/ha): 0S + 100N (?S+N) and 40S + 100N (+S+N) were used. The results showed that combined application of S and N (+S+N) significantly (P < 0.05) increased the nitrogen accumulation in both the genotypes at all the growth stages compared with N applied alone (?S+N). This increase in nitrogen accumulation was due to the improvement in the reduction of nitrate into reduced nitrogen as evident from higher nitrate reductase (NR) activity in the leaves of plants grown with both S and N, compared with N alone. Nitrate-N content in the leaves of plants grown with only N (?S+N) was higher compared to those grown with both S and N (+S+N), showing that combined application of S along with N (+S+N) appreciably reduced the nitrate content in the leaves due to higher NR activity. This decline in nitrate (NO₃ ^?) was followed by an overall increase in N-accumulation in the plants. Consequently, the nitrogen content in the plant was increased by 29–148% in rapeseed and 38-166% in taramira with +S+N treatment. Combined application of S along with N (+S+N) also increased seed protein content and nitrogen harvest index of both the genotypes. It is concluded that combined application of S along with N (+S+N) not only increased the N-accumulation, but also its mobilization towards economic sinks.     

Relationship between Selenium and Sulfur Assimilation and Resultant Interaction on Quality Parameters in Onion

The relationship between selenium (Se) and sulfur (S) uptake and their interaction on the pungency and quercetin contents of onion was investigated in a sand culture trial under polyhouse conditions. The results indicated that application of Se with increasing rates produced an antagonistic effect on S assimilation. An amount of 20 kg Se ha^–1 drastically reduced the S content in onion bulbs. Further, the pungency and quercetin concentration also declined. Foliar application of Se at 1.0 ppm resulted in production of bulbs with lower levels of pungency and quercetin. Though Se is essential from a health point, its application up to 10 kg ha^–1 was sufficient for enriching onions without much effect on the other essential bulb quality parameters.     

Effect of Varying Nitrogen Regimes on Growth,Seed Yield,and Nutrient Accumulation in Isabgol

A greenhouse experiment was conducted to determine the optimum dose of nitrogen (N) fertilizer for attaining maximum yield of isabgol (Plantago ovata Forsk.). Sixty three-day-old plants were subjected to varying levels of N (0, 30, 60, and 90 kg N/ha) until seed harvesting. Maximum growth and seed yield occurred at 60 kg N/ha, whereas 90 kg/ha was inhibitory to isabgol growth. The growth and seed yield recorded at 30 or 60 kg N/ha did not differ much, and in view of the high cost to be incurred from applying 60 kg N/ha and the relatively low yield achieved at this level, 30 kg N/ha would be a much more suitable level for isabgol. Accumulation of N, potassium (K), and phosphorus (P) in shoots or roots of isabgol increased consistently under increasing levels of N, but this pattern of increase in the levels of three nutrients in plant tissues was negatively associated with the growth of the crop, particularly at the supra-optimal N level (90 kg N/ha).     

施氮量和采收株高对油菜薹外观性状、养分积累和氨基酸组分含量的影响

为明确施氮量和采收株高对油菜薹外观性状、养分积累和氨基酸组分含量的影响,以油蔬两用型油菜品种富硒1号为材料,采用裂区试验设计,以施氮量为主区,采收株高为副区,测定了油菜薹粗度和鲜重,氮(N)、磷(P)和钾(K)浓度,硝酸还原酶(NR)、谷酰胺合成酶(GS)和天冬酰胺合成酶(AS)活性,亚硝酸盐含量以及16种氨基酸组分含量。结果表明,随着采收株高的增加,油菜薹粗度降低,但施氮量对油菜薹粗度影响不显著;增施氮肥增加了油菜薹鲜重;在各施氮量处理下,采收株高30 cm时,油菜薹鲜重高于其他采收株高。油菜薹N和K浓度随着施氮量的增加先增加后减小,而施氮量对油菜薹P浓度影响不显著。氮代谢过程中NR活性随着施氮量的增加呈先增加后减小的趋势,与氮素浓度变化一致;而GS和AS活性则表现为持续降低。在采收株高20和30 cm处理下,油菜薹氨基酸组分含量主要随施氮量的增加而显著增加;采收株高40 cm时,油菜薹中的缬氨酸等7种氨基酸含量在各施氮量处理下差异不显著,天冬氨酸等8种氨基酸含量在施氮量180 kg·hm^-2处理下最高,采收株高50 cm时,谷氨酸等4种氨基酸含量在施氮量180 kg·hm^-2处理下最高,其余氨基酸组分含量在各施氮量之间无显著差异。综上,在施氮量180 kg·hm^-2、采收株高40 cm时油菜薹具有较好的品质。本研究结果为油蔬两用型油菜薹优质栽培提供了技术参考。     

液培条件下氮素形态和化控技术对蔬菜硝酸盐累积的影响

以生菜和青菜作为供试材料,在液培条件下,研究了不同形态N素对蔬菜硝酸盐累积的影响,同时观测了叶面喷施两种低硝酸化剂的化控技术对降低蔬菜硝酸盐积累的效果.研究结果表明:N素形态对生菜的生长和硝酸盐的积累影响显著,而对青菜的影响不显著;相同形态N素供应时,青菜叶片中硝酸盐含量显著高于生菜中的含量,硝酸盐的积累取决于不同蔬菜品种的遗传特性.青菜和生菜叶面喷施两种低硝酸化剂对降低蔬菜中硝酸盐含量的作用不显著.     

Nitrogen,Phosphorus, and Sulfur Nutrition in Broccoli Plants Grown Under Salinity

Broccoli (Brassica oleracea L. var. ‘Italica’) is a recognized health-promoting vegetable and shows a moderate sensitivity to salinity. As very little is known about the effect of salt stress on broccoli plants, the objective was to evaluate nitrogen (N), phosphorous (P), and sulfur (S) nutrition in plants grown under saline conditions. For this objective, the contents of nitrate, phosphate, and sulfate, and total nitrogen, phosphorus, and sulfur, as well as related metabolic enzymes, were determined for plants grown with 0, 20, 40, 60, 80, or 100 mM sodium chloride (NaCl) for two weeks. Nitrate, phosphate, and sulfate concentration in leaves and roots showed a maximum at 40–60 mM NaCl. Up to these salt levels, broccoli plants showed a normal development, but over these salt levels, broccoli plants showed a decrease of nitrate reductase and an increase of the acid phosphatase. From 60 to 100 mM NaCl, the nutritional disorders indicated that the threshold of resistance was exceeded.     

Response of Wheat Cultivars to Nitrogen and Sulfur for Crop Yield,Nitrogen Use Efficiency,and Protein Quality in the Semiarid Region

ABSTRACT

The effects of nitrogen (N at 0, 100 and 180 kg N ha-1) and sulfur (S at 0, 20, 40 and 60 kg S ha-1) on crop yield, nutrient uptake, nitrogen use efficiency (NUE), and amino acid composition of two bread wheat cultivars, ‘Shehan’ and ‘Enkoy,’ grown in Andisols and Cambisols in randomized blocks with three replications were evaluated. Both cultivars responded significantly (P < 0.05) to N and S applications and S application with N improved the NUE by 28%. The yield increase for the two cultivars by N and S application ranged between 0.8 to 2.4 Mg ha^?1. The N concentration increased significantly from N0 to N2 in both cultivars. Sulfur fertilization increased the concentration of cysteine and methionine by 27% and 14%, respectively, as compared to N alone. The grain yield, NUE, N, and S uptake, and the S-amino acid concentration of ‘Enkoy’ were significantly higher than ‘Shehan’ cultivar.     

施氮量和株高采收时期对油蔬两用型油菜菜薹糖分积累的影响

为明确氮肥用量和采收株高影响油蔬两用型油菜品种菜薹糖分积累的机制,以富硒1号油菜品系为材料,采用裂区试验设计,研究了3个氮肥水平(120、180和240 kg·hm^-2)和4个采收株高(20、30、40和50 cm)对菜薹糖组分含量的影响,比较了菜薹中蔗糖代谢关键酶转化酶(INV)、蔗糖合成酶(SS)和磷酸蔗糖合成酶(SPS)活性的变化,并对糖代谢关键酶活性基因的表达量进行了分析。结果表明,淀粉含量随着施氮量的增加而降低,其他糖分含量在施氮量为180 kg·hm^-2时显著高于其他施氮处理,表明过高和过低施氮量均不利于菜薹糖分积累。就不同采收株高而言,菜薹中果糖、淀粉、葡萄糖和蔗糖含量在株高20 cm采收时最高;海藻糖和山梨醇含量在株高40 cm采收时显著高于其他处理。菜薹SPS活性在各施氮量和采收株高处理下均比INV和SS活性低,表明菜薹中蔗糖以分解成小分子单糖如葡萄糖、果糖等代谢活动为主。在菜薹各采收时期和施氮量处理下,蔗糖分解体系的蔗糖合成酶SUS1/SUS4、SUS3和转化酶A/N-INVA、CINV1、CINV2等基因表达模式互补且为上调,增强了蔗糖的分解,而对蔗糖磷酸合成酶SPS1/SPS2的表达量影响很小。本研究结果为油蔬两用型油菜薹品种合理氮肥运筹提供了理论依据。     

谷胱甘肽对小麦幼苗铜毒害的缓解作用及其与氮、硫、磷积累的相关性

采用水培法,对外源谷胱甘肽（GSH）缓解小麦幼苗铜毒害及其与氮、硫、磷等元素积累的相关性进行了研究。结果表明,Cu处理（T0组）显著抑制小麦幼苗的生长发育,导致根长、茎叶长、生物量、叶绿素和类胡萝卜素含量以及氮元素积累量下降,诱导了植株蛋白质、内源GSH含量以及硫、磷元素积累量上升。随施用外源GSH浓度的升高,GSH处理（T1、T2、T3组）的小麦幼苗茎叶长、根长、生物量,叶绿素a、b和类胡萝卜素含量、蛋白质含量先上升后下降,内源GSH含量以及氮、硫、磷等营养元素积累量持续上升;其中,T2组小麦幼苗的各项指标与T0组差异均达到显著水平（P〈0.05）,与对照组（CK）无显著差异。外源GSH促进了植株对铜离子的吸收、转运和积累,而外源和内源GSH均与铜胁迫下小麦幼苗氮、硫、磷等营养元素的积累呈极显著正相关（P〈0.01）,其中以T2处理组缓解小麦幼苗铜毒害的作用最显著。     

Effect of Sodium Chloride on Growth,Nutrient Accumulation,and Nitrogen Fixation of Common Bean Plants in Symbiosis with Isogenic Strains

The effect of sodium chloride (NaCl)-salinity on growth responses and tissues organic solutes and mineral content was investigated in common bean plants inoculated with salt-tolerant Rhizobium tropici wild-type strain CIAT899 and four mutant derivatives having decreased salt-tolerance (DST). Under non-saline conditions two mutants formed partially effective (HB10, HB12) and another two almost ineffective (HB8, HB13) nodules. A great variation of NaCl tolerance in the different symbiosis tested was observed at harvest, 32 day after planting. Common bean plant responded to salinity by decreasing the content of dry plant biomass, nodule number and the nitrogen fixation, and increasing the root to shoot ratio. The salt dose of 25 mM produced an increase of total soluble sugar and free amino acids content. This result suggest that these metabolites might be related with a nodule osmotic adjustment response under saline conditions, however cannot be excluded that the increase of amino acids content could be a consequence of protein degradation. In the other hand, sodium, calcium and phosphorus contents in shoot increased under the saline treatments. Potassium (K) and calcium (Ca) contents, unlike phosphorus (P) content, in shoot were not related with the symbiotic efficiency of mutant, however the decrease of P content suggest that these symbioses have limited their P absorption process independently of the saline treatment. NaCl tolerance associated with a retention of sodium and maintenance of potassium selectivity seem to be a strategy used for the salt stressed common bean plants in symbiosis assayed here.     

Nitrogen Levels Influence Biomass,Elemental Accumulations,and Pigment Concentrations in Spinach

ABSTRACT

Spinach (Spinacia oleracea L.) has one of the highest United States per capita consumption rates among leafy vegetable crops, and also ranks second for lutein and β-carotene carotenoid concentration. The objectives of this study were to determine the effects of nitrogen (N) concentration on elemental and pigment accumulation in spinach. Two spinach cultivars (‘Melody’ and ‘Springer F1’) were greenhouse grown in nutrient solution culture under N treatments of 13, 26, 52, and 105 mg L^{? 1}. Leaf tissue biomass increased from 45.6 to 273.2 g plant^{? 1} and from 127.0 to 438.6 g plant^{? 1} as N increased from 13 to 105 mg L^{? 1} for ‘Springer F1’ and ‘Melody’, respectively. Leaf tissue N, phosphorus (P), calcium (Ca), magnesium (Mg), copper (Cu), and zinc (Zn) responded to N treatments. Lutein accumulations, expressed on a fresh weight basis, responded quadratically to increasing N treatments for ‘Springer F1’. Maximum lutein values were 110 and 76 μ g g^{? 1} on a fresh weight basis, and maximum β-carotene values were 85 and 57 μ g g^{? 1} on a fresh weight basis for ‘Springer F1’ and ‘Melody’, respectively. Interestingly, N levels had a significant effect on carotenoid accumulation in both ‘Springer F1’ and ‘Melody’ when the pigments were expressed on a dry weight basis. Leaf tissue lutein increased from 0.59 to 1.06 mg g^{? 1} and from 0.59 to 0.90 mg g^{? 1} on a dry weight basis with increasing N treatments for ‘Springer F1’ and ‘Melody’, respectively. Reporting lutein and β-carotene on both a fresh and dry weight basis may be the most accurate way to express the carotenoid values of spinach.     

淮北砂姜黑土区氮钾配施对小麦产量及氮、钾养分吸收利用的影响

为给淮北砂姜黑土区小麦生产中氮、钾肥的科学施用提供理论与技术依据,采用田间试验研究了不同氮、钾水平(N:180、240、300、360 kg·hm~(-2);K:90、135、180 kg·hm~(-2))对小麦产量、氮钾养分吸收利用以及肥料效益的影响。结果表明:(1)N_(240)K_(180)处理下小麦产量为7 686 kg·hm~(-2),比低氮低钾(N_(180)K_(90))处理的小麦产量显著提高7.24%,与高氮高钾(N_(360)K_(180))处理的小麦产量无显著性差异;(2)氮、钾肥配比施用时两者存在正交互作用,该交互作用与小麦产量呈极显著正相关,对产量的贡献率为14.06%,且提高了氮、钾肥的偏生产力;(3)与低氮低钾(N_(180)K_(90))处理相比,N_(240)K_(180)处理下小麦植株体内氮、钾素含量分别提高14.67%和29.53%。综合考虑小麦产量和肥料效益,本研究条件下淮北砂姜黑土区适宜的氮(N)、钾(K_2O)肥施用量分别为240 kg·hm~(-2)和180 kg·hm~(-2)。     

Influence of Nitrogen and Potassium Supply on Contents of Acrylamide Precursors in Potato Tubers and on Acrylamide Accumulation in French Fries

Fried potato products may accumulate substantial amounts of acrylamide due to high precursor contents, namely reducing sugars and asparagine. In a two-factorial experiment increasing N supply, increased the contents of reducing sugars in most cases, and resulted in higher contents of free amino acids. α -amino-N, which was tightly correlated with the contents of free amino acids, can be regarded a suitable rapid test for free asparagine for a given variety. Increasing K addition always raised the citrate contents, but lessened the contents of reducing sugars. Selected treatments were processed into French fries. Highest acrylamide contents were observed in tubers grown with high N and inadequate K supply, which also contained the highest contents of precursors. The experiment clearly demonstrates that nutrient supply has significant impact on the contents of acrylamide precursors and thus for the acrylamide formation during frying.     

氮添加对滇中高原森林凋落物养分残留及其持水性的影响

为揭示森林生态系统养分循环和水分循环对氮沉降的响应机制,以滇中高原华山松(Pinus armandii)和云南松(Pinus yunnanensis)为研究对象,开展野外氮添加下凋落叶、枝原位分解研究试验,设置对照、低氮、中氮和高氮共4个处理,利用尼龙网袋法和室内浸泡法,探究凋落叶、枝养分元素残留率、持水量和持水率及吸水速率对氮添加的响应。结果表明:(1)随着分解时间的持续,2种林分凋落叶、枝碳(C)、氮(N)、磷(P)分别呈释放、富集—释放、富集过程,凋落叶C、N、P残留率显著小于凋落枝(p＜0.05);(2)凋落叶最大持水量和最大吸水速率显著大于凋落枝(p＜0.05),分解24个月时,与CK相比,LN处理下2种林分凋落叶、枝C,华山松凋落叶N残留率降低1.98%~7.27%,10.79%,HN处理下2种林分凋落叶、枝C,华山松凋落叶、枝和云南松凋落枝N,华山松凋落枝P残留率则增加4.26%~9.08%,11.94%~44.51%,42.42%;(3)分解24个月时,与CK相比,LN、MN和HN处理华山松凋落叶、枝和云南松凋落叶最大持水量和最大吸水速率分别降低11.44%~25.24%,5.81%~32.23%,云南松凋落枝则增加15.48%~24.26%,17.97%~23.74%。 (4)2种林分凋落叶、枝持水量随浸泡时间延长而增加,而吸水速率则为降低,持水量与浸泡时间的关系均呈对数函数关系(m=a+bln t),吸水速率与浸泡时间的关系呈幂函数关系(v=at^-b)。(5)C与云南松凋落枝持水性呈正相关关系(p＜0.05),N与华山松凋落枝、P与华山松和云南松凋落叶持水性呈负相关关系(p＜0.05)。综上,氮添加通过改变凋落物分解过程中C、N、P养分元素残留特征进而影响其持水性。     

水氮调控对休耕期土壤养分迁移及翌年土壤肥力的影响

为研究河套灌区盐碱农田不同施氮量在冻融作用后对翌年春播前土壤肥力的影响效应,结合翌年土壤肥力状况确定当地适宜的施氮量。采用田间试验的方法,共设置4个施氮水平(高氮N_3:325 kg/hm^2;中氮N_2:225 kg/hm^2;低氮N_1:125 kg/hm^2;不施氮N_0)研究冻融期内水盐时空分布、全氮、碱解氮以及有机质含量的变化规律,并采用主成分分析法对翌年春播前土壤肥力进行综合评价。结果表明:(1)秋浇后,土壤含水率显著高于秋浇前,表层土壤含水率增加,开始冻结时,水分向表层积聚,随着温度降低水分自表层向深层冻结,各处理灌溉水平相同,不同施氮处理之间对土壤含水率的影响不显著,土壤墒情满足作物对水分的需求;秋收后耕层土壤含盐率随生育期内施氮量的增加而增加,施氮量越大土壤含盐率递增。秋浇后大量盐分被淋洗,融化后盐分受到融冻水的下渗和蒸发的共同作用,使得各处理表层含盐率为N_0(0.14%)相似文献   

黄土高原丘陵沟壑区植被恢复过程对土壤剖面矿质氮累积影响--以纸坊沟流域试验区为例

根据不同植被类型和不同植被恢复年限,在位于半干旱黄土高原丘陵沟壑区延安安塞纸坊沟流域采集68个剖面样品,探讨植被恢复过程土壤剖面中残留矿质态氮的变化;同时采取该流域连续14年施用不同肥料处理的坡地长期定位试验剖面土样,研究连续施肥对农田土壤剖面残留NO3--N累积的影响。结果表明,NH4 -N在土壤剖面中的分布和累积基本不受植被恢复及植类型的影响,但NO3--N在土壤剖面中的累积量随植被恢复而下降。林地、草地和农田0～50cm土层平均累积的NO3--N分别为17 4kg/hm2,14 9kg/hm2和39 9kg/hm2;林地和草地剖面中NO3--N累积量所占矿质氮总累积量比例远小于NH4 -N,而对农田土壤,剖面中NO3--N累积量所占比例与NH4 -N所占比例基本相当;农田土壤剖面中NO3--N累积量所占比例显著大于林地和草地。长期定位试验结果进一步证明了在农田连续施用氮肥会显著增加土壤剖面中残留NO3--N累积,当农田退耕还林还草后,累积的这一部分NO3--N因植物吸收利用、土壤生物固定和损失等途径而下降,最终达到低而稳定的水平。     

大气O_3升高对小麦根际土壤微生物量和氮素转化酶活性的影响

通过开放式臭氧浓度升高试验平台(FAOE)对扬麦16(臭氧耐受品种)和烟农19(臭氧敏感品种)根际土壤氮转化相关酶活性进行研究。结果表明:臭氧熏蒸5年后,小麦根际蛋白酶活性未发生显著变化;敏感品种根际脲酶活性增高4.01%;氨氧化酶活性在敏感和耐受品种根际土壤中分别提高19.38%和203.66%,土壤NH_4~+和NO_3~-显著升高,但微生物量氮显著下降;硝酸还原酶和亚硝酸还原酶活性分别呈现下降和升高的趋势,这种变化在臭氧敏感品种土壤中更显著。冗余分析表明,全氮、臭氧和pH是显著影响这5种酶活性的最主要因素。试验的结果表明,在大气臭氧浓度升高条件下,小麦根际氮循环会在酶的调节下发生变化,可能会增加土壤氮素以温室气体N_2O和硝酸盐形式损失的风险,且臭氧敏感品种根迹土壤变化更显著。     

Crop Nutrient Status and Nitrogen,Phosphorus, and Potassium Balances Obtained in Field Trials Evaluating Different Fertilizer Recommendation Systems on Various Soils and Crops in Hungary

Based on correlations calculated from the database of long-term fertilization experiments carried out in Hungary between 1960 and 2000, a new, cost-saving, and environmentally friendly fertilizer recommendation system was developed. The aim of the new system is to apply the lowest possible nitrogen (N)–phosphorus (P)–potassium (K) rates required to achieve good yields and maximum income per unit area. The World Phosphorus Institute (IMPHOS) agreed to finance a 3-year program to test various Hungarian fertilizer recommendation systems (the new RISSAC-RIA [Research for Soil Science and Agricultural Chemistry‐Research Institute for Agriculture] system, the Talajer?gazdálkodás integrated soil fertility management system, and the intensive MÉM NAK [Department of Plant Protection and Agricultural Chemistry of the Ministry of Food and Agriculture] system) when applied to three major crops grown on three characteristic Hungarian soils. The first five treatments in the experiment represented a classical deficiency experiment, aimed at checking the correctness of the NPK supply categories determined by the various systems. On all three soils and for all three crops the IMPHOS experiments confirmed the basic principles of the new cost-saving, environmentally friendly fertilizer recommendation system and the correctness of the methods used for calculating fertilizer rates. In this article, diagnostic plant analysis, soil analysis data, and NPK balances obtained in the different recommendations are discussed. In most cases the plant NPK contents of all the recommendations exceeded the lower limits of the good NPK supply category for wheat and barley shoot as well as for corn leaf. Crop NPK contents in Talajer?gazdálkodás and MÉM NAK treatments (with greater recommended NPK doses) were most cases better than in the RISSAC-RIA treatments; however, the better crop NPK status did not result in extra grain yield in the former treatments. Taking into account that similarly high yields were obtained using the RISSAC-RIA system and the Talajer?gazdálkodás integrated system with much smaller NPK doses than those recommended by the intensive MÉM NAK system, it was more advantageous from agronomic, environmental protection, and economic points of view. Differences in PK balances correlated well with the differences in the measured soil ammonium lactate (AL)–PK contents after the third year of the experiment.     

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.