Growth,yield and bulb quality of onion (Allium cepa L.) in response to foliar application of boron and zinc

A field experiment was conducted to investigate the role of boron and zinc on growth, yield and quality of onion. There were eight treatment combinations consisted of four levels of boron (0, 0.1, 0.2 and 0.5%) and 4 levels of zinc (0, 0.1, 0.2 and 0.5%) were applied as foliar spraying. application of 0.5% boron significantly increased the growth (plant height, 63.93cm and number of leaves per plant, 7.25), yield (30.74 t ha^?1) and quality (total soluble solids, 13.45 ⁰B and pyruvic acid 5.94 µmol g^?1) of onion. Among various levels of zinc 0.5% exhibited the best growth (plant height, 67.25cm and number of leaf per plant, 7.75), yield (33.34 t ha^?1) and quality (total soluble solids, 14.57 ⁰B and pyruvic acid, 5.86 µmol g^?1) attributes of onion. These results suggest that the foliar application of boron and zinc significantly influenced the growth, yield and quality of onion.     

Fate of flavonoids in the outer skins of onion (Allium cepa L.) throughout curing

Reducing the current U.K. curing temperature from 28 to 20 °C would help to reduce energy costs; however, onion skin appearance and consumer acceptability may be detrimentally affected. The aim of this study was to elucidate the compounds responsible for the difference in color between brown and red onions cured at 20 and 28 °C by monitoring dynamic biochemical changes in the skin at set intervals during curing and after storage from two years' data. Sugar concentrations appeared to play no role in the difference in onion skin appearance when cured at different temperatures. Using regression, principal component, and partial least-squares discriminant analyses, the decrease in skin H° after the curing of brown onion cultivars at 28 °C was linked to a decrease in individual flavonol concentrations, possibly due to their oxidation at higher temperatures into brown pigmented compounds. Red onion cultivars cured at lower temperatures and for a shorter curing period had higher concentrations of individual anthocyanins as well as a darker skin color. Skin water content was reduced significantly in only the first 6 days of curing. Taken together, this suggests that current U.K. curing practice could be carried out at a lower temperature (20 °C) and/or for a shorter duration, resulting in reduced curing costs and possibly improved skin appearance.     

Structural carbohydrate differences and potential source of dietary fiber of onion (Allium cepa L.) tissues.

Onion tissues of three varieties were evaluated for dietary fiber (DF) composition. Insoluble (IDF) and soluble (SDF) dietary fibers were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Brown skin exhibited the highest total dietary fiber (TDF) content (65.8%) on a dry matter basis, followed by top (48.5%) and bottom (38.6%), IDF being the main fraction found. The SDF:IDF ratio decreased from inner to outer tissues. Brown skin and outer leaves byproducts appear to be the most suitable sources of DF that might be used in food product supplementation. The chemical composition reveals that cellulose and pectic polysaccharides were the main components of onion DF in all tissues, although differences between them were noticed. An increase in the uronic acids/neutral sugars ratio from inner to outer tissues was found, suggesting that the galactan side chain shows a DF solubilization role.     

硅对大葱矿质元素吸收、 分配特性及产量和品质的影响

【目的】大葱因含有机硫化合物等功效成分而具有重要的保健和药用价值,为此,前人曾就氮、 磷、 钾、 硫等矿质元素与大葱产量、 品质及风味物质的关系进行了一些研究。硅作为一种公认的有益元素,在提高作物产量、 改善品质等方面具有重要作用,本试验研究了硅对大葱矿质元素吸收、 分配特性和产量及品质的影响,以期为大葱高效施肥提供科学依据。【方法】本研究以‘天光’和‘章丘’两个不同类型大葱品种为试材,供试硅源均为Na2SiO3·9H2O,通过盆栽Hoagland营养液培养和大田土壤栽培相结合的方法,分别研究了营养液不同硅水平(SiO2 0、 0.6、 1.2、 1.8 mmol/L)和土壤不同施硅量(SiO2 0、 150、 300、 450 kg/hm2)对大葱生长、 产量、 品质及硅、 氮、 磷、 钾含量、 吸收量的影响。【结果】营养液硅水平在1.8 mmol/L范围内,‘天光’和‘章丘’两品种大葱株高、 假茎长、 假茎粗、 植株干重以及单株产量均随硅浓度升高呈先上升后下降的趋势,且均以1.2 mmol/L的处理表现最好,其单株产量分别较不施硅提高了19.4%和30.9%; 适量施硅还显著提高了大葱游离氨基酸、 可溶性糖、 丙酮酸等含量,表明施硅有利于改善大葱品质。随营养液硅水平的升高,两大葱品种各器官硅含量均显著增加,在1.8 mmol/L处理时达最高,而钾含量则与之相反,氮、 磷含量则呈先上升后下降的趋势,均以1.2 mmol/L处理含量较高; 由于施硅促进了大葱生长,所以大葱对硅及氮、 磷、 钾的吸收量则均随硅水平的升高呈增加趋势。大田施硅试验表明,‘天光’和‘章丘’两品种大葱均以施硅量(SiO2)300 kg/hm2时产量较高,分别比对照增产15.4%和25.6%。【结论】大葱增施硅可显著增加大葱对硅及氮、 磷、 钾的吸收量,促进植株生长,提高产量和品质,但同一硅水平的增产率以‘章丘’品种显著高于‘天光’,且二者随硅水平变化的幅度也不相同,表明不同大葱品种对硅的反应敏感性存在显著差异。本试验条件下,以营养液硅水平1.2 mmol/L、 土壤施硅300 kg/hm2时较有利于大葱的生长及产量和品质的提高。     

不同硼水平对双低油菜华双4号产量和品质的影响

以甘蓝型常规油菜品种中油821(双高品种)为对照,通过盆栽试验研究了不同硼水平对甘蓝型双低油菜华双4号子粒产量和品质的影响。结果看出,两个油菜品种在缺硼条件下,施硼量从B 0.3 mg/kg增加到B 2.5 mg/kg时,单株角果数、每角粒数和子粒产量显著增加,但增加到B 5.0 mg/kg时,每株角果数、每角粒数和子粒产量显著降低,硼过量影响产量建成。在硼缺乏和硼过量条件下,华双4号的减产程度均高于中油821,表明双低优质油菜华双4号对缺硼和硼过量的反应较常规双高油菜中油821敏感。硼缺乏或过量时,两个品种子粒含油量和油酸含量均表现降低的趋势,而蛋白质含量呈增加趋势。本试验的结果表明,合理施用硼肥对子粒产量的影响大于对品质的影响,而高产优质品种华双4号更应注重硼肥的合理施用;我国栽培油菜的土壤有效硼的适宜浓度可以提高至B 1.0 mg/kg.但硼肥的安全施用应当控制在土壤有效硼含量为B 2.5 mg/kg以下。     

Complement test for distinctiveness,uniformity and stability testing of kharif onion (Allium cepa L.) varieties

Genetic Resources and Crop Evolution - The distinctiveness, uniformity and stability (DUS) testing is important for varietal identification and protection of plant variety. It has become one of the...     

Soil amendments and seed priming influence nutrients uptake,soil properties,yield and yield components of wheat (Triticum aestivum L.) in alkali soils

The effects of soil amendments [i.e., control, gypsum, farmyard manure (FYM), and gypsum?+?FYM] and seed priming (i.e., unprimed, seed soaked in water for 10?hr prior to sowing, and seed soaked in 0.4% gypsum solution for 10?hr prior to sowing) were assessed on growth and yield of wheat (Triticum aestivum L.) crop in alkali soil in northwestern Pakistan. A split plot design was used, keeping priming methods in main plots and soil amendments in sub-plots. The results showed that the effects of soil amendments and seed priming on grain yield, straw yield, harvest index and number of spikes were significant but their interactive effect was non-significant. The highest crop yields and yield index were obtained with gypsum?+?FYM amendments, and seed priming with gypsum solution. The effect on seed emergence, plant height and number of grains per spike was, however, not significant. Grain yield increased by 104% in gypsum?+?FYM treatment over control and by 16.8% with seed primed in water, followed by 8.5% with priming in gypsum solution, as compared to non-priming. The weight of 1000 grains was significantly increased by 35% in gypsum?+?FYM treatment and by 15.8% in gypsum priming. The phosphorus (P) and potassium (K) content increased with soil amendments. Soil pH and gypsum requirement reduced significantly with soil amendments. The blend of gypsum and FYM has improved the properties of salt-affected soil and enhanced fertility for optimum production of wheat in addition to the beneficial effect of seed priming in gypsum solution on crop yield. Using these amendments could be ameliorative in removing the adverse effect of the salt-affected soils, rendering the soil a good medium for plant growth.     

Effect of nitrogen application on seed yield,pod and seed characteristics of okra

Four okra cultivars [Abelmoschus esculentus (L.) Moench] were cultivated for two growing periods at nitrogen (N) application rates of 150, 300 and 450 mg N L^?1. There was no effect of N on pod size (length and diameter) or on the number of seeds per pod and seed size (mean 1000 seed weight), all these characteristics of which related to the genotype. High N application (450 mg N L^?1), increased the seed yield of the cultivar with the lowest flower induction (Boyiatiou), but only in experiment 2. In Veloudo, seed yield was highest at 300 mg N L^?1, whereas in Pylaias and Clemson 450 mg N L^?1 reduced seed yield. In all cultivars, seeds produced at an N rate of 450 mg N L^?1 exhibited a significantly higher percent germination N, possibly by reducing the incidence of seed hardness.     

Effect of organic foliar spray with pulse sprout extract on seed yield and quality of rice (Oryza sativa)

Organic seed is the basic for organic agriculture, since it is a crucial link in the chain from research, breeding, seed production, to organic production. With organic seeds the grower can complete the chain of organic input. To develop an organic foliar spray technique and for organic seed production, experiments were carried out to study the effect of organic foliar spray with pulse sprout extract on rice. In this study, horse gram and cowpea, the unexploited legumes of the tropics with high nutritional quality and comparatively low cost were used for preparing the pulse sprout extracts, an organic foliar spraying material. Higher accumulation of bioactive substances in sprouted seeds offers immense scope to develop an inexpensive and effective organic foliar spray technology so as to achieve better crop growth and higher seed yield of rice, the major staple food of the world. The biochemical analysis was done in both extracts to estimate the total antioxidants activity, soluble protein content, total soluble sugars, ascorbic acid content and minerals like nitrogen, phosphorus, potassium, calcium, iron and zinc. Subsequently, the effect of pulse sprout extract spray in improving crop growth, tillering, productivity, and resultant seed quality of was studied by spraying on the parental lines of rice hybrid CORH3 (A, B and R lines) and rice variety CR 1009. The experiment consisted of four trials. In the first trial, four concentrations of pulse extract (1, 2, 3, and 4%) were evaluated in the R line (medium duration variety) of CORH3 (medium duration). In the subsequent trials, the best concentrations (2 and 3% for horse gram and 1 and 2% for cowpea), determined from the first trial, were evaluated again in two medium duration lines of B line multiplication (AXB) and hybrid seed production (AxR). The fourth trial was done with a long duration variety namely CR 1009. Spraying of pulse sprout extract significantly improved majority of the growth and yield attributes culminating in significantly higher seed yield, in all the four trials. The study firmly revealed foliar sprays with either 3% horse gram sprout extracts or 2% cow pea sprout extract during active tillering and seed filling stages of rice crop, can significantly increase the growth and yield attributes, eventually resulting in higher seed yield, irrespective of the cultivars. It could be concluded that foliar spraying of 3% horse gram sprout extract or 2% cow pea sprout extract at active tillering stage and seed filling enhances seed yield attributes and yield in rice.     

Quercetin and isorhamnetin glycosides in onion (Allium cepa L.): varietal comparison, physical distribution, coproduct evaluation, and long-term storage stability

During onion processing, the outer dried protective layer (outer paper layer) and first two fleshy leaf layers are removed. This coproduct material is a potential commercial source of flavonoids especially quercetin. In the following study, the flavonoid composition was determined in coproduct materials and the press cake (material generated after juice extraction) in several commercially important onion varieties grown in California. Flavonoids were characterized and quantified using LC-(ESI)MS/MS and HPLC. The long-term stability of quercetin glycosides was assessed in dried coproduct materials stored at 4 and 22 °C over a 12 month period. In all varieties, the predominant forms of quercetin were the quercetin 3,4'-O-glucoside and 4'-O-glucoside. The first layer had significantly higher levels of flavonoids than the outer paper, second, and inner flesh layers on a DW basis (p < 0.05). Allium cepa "Milestone" contained the highest levels (p < 0.05) of flavonoids (1703 mg/100 g on a dry weight basis (DW). Onion press cake had significantly higher levels of total quercetin as compared with fresh onions (p < 0.05). The levels of 4'-O-glucoside significantly decreased during the first month of storage and remained stable for 12 months of storage at either 4 or 22 °C (p < 0.05).     

Effect of seed phosphorus and soil phosphorus applications on early growth of rice (Oryza sativa L.) cv. IR66

Abstract

The vigour and size of rice seedlings in the nursery are generally correlated with final grain yield. The present study examined the possibility that increasing seed phosphorus (P) concentration would stimulate early growth of rice seedlings and therefore would have the potential to increase rice yield. Rice seeds with a uniform size and three levels of P concentration (0.115, 0.173, and 0.240% on a dry weight basis) were sown in pots on a P deficient soil with three levels of P supply (0, 7.75, and 38.8 mg P kg^?1 soil) to investigate their effect on root and shoot dry weight and P accumulation at three harvest times, 10, 20, and 30 d after sowing (DAS). The effect of seed P concentration on plant growth was greatest at a low soil P concentration and it was less pronounced with increasing soil P concentration and with time at all levels of soil P. At 10 DAS, shoot dry weight was 15% higher at a high seed P concentration (0.240%) (p < O.O1) than at a low seed P concentration (0.115%) at each level of soil P supply whereas at subsequent harvests (20 and 30 DAS) the effect of seed P concentration was observed only when the soil P supply was deficient. In contrast with its effects on shoot dry weight, high seed P concentration increased root dry weight only at the latest harvest (30 DAS). The fact that high seed P increased P concentrations in shoot tips, and in roots at 10 DAS suggests that improved P nutrition of seedlings in the first 10 DAS may be the mechanism by which high seed P concentration stimulates early growth, especially in soils with low P concentration. Sowing rice seed with high P concentration may be beneficial for increasing farmer's rice yields, in P deficient soil, and requires further field investigations.     

Selection at the Ms locus in open pollinated onion (Allium cepa L.) populations possessing S-cytoplasm or mixtures of N- and S-cytoplasms

The bulb onion (Allium cepa L.) was historically seed propagated by open pollination (OP). Cytoplasmic-genic male sterility (CMS) and protandry encourage outcrossing among individual onion plants. The most common source of CMS in onion is conditioned by the interaction of sterile (S) cytoplasm with a single nuclear male-fertility restoration (Ms) locus. We previously reported that the majority of OP onion populations possess normal (N) male-fertile cytoplasm and varying frequencies of the dominant Ms allele. It was unclear why N-cytoplasmic onion populations often possess relatively high frequencies of the Ms allele, which has no obvious function. We used computer simulations to estimate changes in allelic frequencies at Ms for onion populations possessing S-cytoplasm or a mixture of N- and S-cytoplasms, and to determine if frequencies of the Ms allele stay constant or change due to failure of male gamete production from male-sterile (S msms) plants. The models revealed selection against the recessive ms allele over generations in onion populations possessing S-cytoplasm and varying amounts of self pollination and inbreeding depression. These models were consistent with field and molecular analyses documenting that N-cytoplasm and the dominant Ms allele predominate in OP onion populations.     

Temperature requirements for seed germination in species of the genus Allium L.

For taxonomic purposes and because many wild relatives of Allium crops are endangered in their native habitat (Sancir et al., 1989), a collection of Allium species was built up in the IPK at Gatersleben. At present it consists of more than 3000 accessions representing about 330 species. In this context it was necessary to study the seed germination behaviour and dormancy of certain wild Allium species. Therefore, seeds of 91 wild and three cultivated Allium species were tested at germination temperatures of 5°, 11°, 16° and 26°C. The purpose of this study was to develop routine germination tests for the genebank work with wild alliums.     

Interaction of mineral and cytokinin supply in control of leaf senescence and seed growth in soybean explants

Abstract

The leaves of intact soybean plants (Glycine max. L. Merrill) characteristically turn yellow and abscise during pod maturation, and this may limit seed growth. We have used soybean expiants (excised 10 cm stem sections with a leaf and midfill pod attached) to study interactive effects of nutrient and hormone supply on leaf senescence symptoms and seed yield. Whereas mineral nutrients or cytokinin (zeatin) alone delayed development of visible leaf senescence symptoms in explants, a combination of mineral nutrients with zeatin acted synergistically to maintain green coloration throughout pod maturation and reduced declines in levels of leafsoluble protein and chlorophyll. The combination of complete mineral nutrients with zeatin gave seed yields equivalent to those in intact plants. Withdrawal of zeatin or individual mineral nutrients (particularly N and S) from the nutrient solution enhanced leaf senescence symptoms and reduced seed yields.     

Effects of combined application of vermicompost and mineral fertilizer on the growth of Allium cepa L. and soil fertility

The promotion of organic farming involves curtailing extensive use of mineral fertilizers. The present study was aimed to compare the effects of vermicompost (10 Mg ha^–1), commercial mineral fertilizer (NPK—100:80:80), and their combination on (1) the growth of a major cash crop “onion” (Allium cepa L.) and (2) the changes that may have occurred in the amended soil. The experiment was a randomized complete block design with four replications during the crop‐growing season of 2008/09. Results showed significantly higher plant growth in the combined/mix treatment of vermicompost and NPK, as measured by the vegetative growth of bulbs, number and length of tillers per bulb, and fresh weight of bulbs and by the biochemical characteristics of the onion tillers/leaves (total chlorophyll, caretenoids, protein, and total sugar contents). Comparison of the mixed treatment as compared to the control showed increases in bulb size (54%), total number of bulbs per bed (52%), and fresh weight of all bulbs (198%). The chemical properties and enzyme activity of the amended soil also improved significantly in the combined treatment as compared to the application of vermicompost or the mineral fertilizer alone. Total organic C, microbial biomass C, and sulfate content were significantly higher in the mix treatment, with increases of 60%, 127%, and 126%, respectively, as compared to those of the chemical‐fertilizer‐alone treatment. Similarly, β‐glucosidase, alkaline phosphatase, and dehydrogenase were significantly higher by 145%, 91%, 71%, respectively, in the mix treatment as compared to those of fertilizer‐alone application. This study indicates that application of a combination of mineral fertilizer and vermicompost in the field can positively influence the biological properties and fertility of soils, and support better plant growth, when compared to the application of mineral fertilizer or vermicompost alone. The study suggests that this combined application can reduce the quantity and cost of mineral‐fertilizers application for bulbous‐crop cultivation by 50%, while also sustaining soil biological activity of tropical and subtropical soils.     

栽培模式对直播油菜生长、产量和养分吸收利用的影响

发展直播油菜对增加我国油菜种植面积和总产有重要意义,但栽培措施尤其是施肥技术的滞后极大地影响了油菜的产量及施肥效果。2009/2010年度在湖北省油菜主产区设置田间试验,研究栽培模式对直播油菜生长、产量、经济效益和养分吸收利用的影响,探讨适合当前生产的高产高效栽培技术。结果表明,各优化模式比农民习惯栽培模式均有增产增收效果,其中在30104 plant/hm2种植密度、秸秆还田和加强病虫草害防治的基础上进行优化施肥（氮、磷、钾肥用量分别为N 195 kg/hm2、 P2O5 90 kg/hm2、K2O 90 kg/hm2,硼砂用量15 kg/hm2,氮肥和钾肥分次施用）的模式Ⅲ表现最好,比农民习惯施肥增产35.9 %、增收1632 Yuan/hm2,地上部干物质量和养分累积也均较高,氮、钾肥偏生产力分别为N 13.7 kg/kg和K2O 29.8 kg/kg,实现高产高效目标。说明当前直播油菜的栽培模式应结合其生长发育进程和养分吸收规律,适当密植以增库促源,加强植保防治病虫草害,更重要的是积极推行平衡施肥和有机、无机配施,并合理安排施肥时期及比例。     

Pink-pigmented facultative methylotrophic bacteria accelerate germination, growth and yield of sugarcane clone Co86032 (Saccharum officinarum L.)

The existence of Methylobacterium as a symbiont with sugarcane and its influence on crop growth at various stages was examined. Pink-pigmented facultative methylotrophic bacteria (PPFMs) strains isolated from different parts of the sugarcane clone Co86032 showed growth on methanol, and were further confirmed based on the mxaF gene encoding the -subunit of the methanol dehydrogenase by polymerase chain reaction amplification using specific primers. True seeds inoculated with PPFMs had a higher germination percent and rate of germination than the control. A combined treatment of seed imbibition, soil application and phyllosphere spray increased specific leaf area, plant height, number of internodes, and cane yield. Immunological determination of cytokinin in young and mature leaves significantly increased when the epiphytic population on the leaf surface increased. Trends in sugar qualities in the form of Pol (sucrose) % in cane, Brix % in cane, and commercial cane sugar were similar to that of cane yield. These effects might be mediated by the production or synthesis of plant hormones.     

Contribution of roots and hyphae to phosphorus uptake of mycorrhizal onion (Allium cepa L.)—A mechanistic modeling approach

Phosphorus uptake by plant roots and arbuscular mycorrhizae (AM) hyphae can be described based on morphological and physiological uptake characteristics and parameters affecting P transport in the soil to the uptake surface. The current study aimed to quantify the relative contribution of hyphae and roots to P uptake of onion and to investigate the associated mechanisms using a mechanistic simulation model. Onion was grown in a growth chamber under controlled conditions at five levels of P supply with (M) or without (NM) AM. Uptake by onion roots and AM hyphae was simulated separately using a nutrient‐uptake model, which was developed for roots. Model parameters describing P transport in the soil, as well as morphological and physiological uptake characteristics of roots and hyphae were derived from soil and nutrient‐solution experiments. The model fairly described P uptake of M and NM plants at the highest level of P supply (28 µM P in soil solution) where roots and hyphae contributed nearly equally to P uptake of M plants. However, at lower P levels (≤0.41 µM P), hyphae accounted for nearly the whole P uptake whereas roots hardly explained any uptake. The effectiveness of AM hyphae at low P supply was well explained by their favorable morphological and physiological uptake properties. Hyphae were characterized by a diameter of 3 × 10^–4 cm, a K_m of 0.25 µM, and a C_min of 0.04 µM, values that are about 200, 40, and 10 times lower, respectively, compared to those of roots. Not more than 60% of the uptake at lower levels of P supply could be explained by the sum of predicted uptake of roots and hyphae suggesting that hyphae and roots may have used mechanisms additional to those described by the model to mobilize P. This work demonstrated that mechanistic models can be useful tools to study the role of AM in P uptake of plants, although reliable estimation of model parameters, especially physiological uptake properties of AM, is still limiting this approach.     

Mycorrhizal influence on storage metabolites and mineral nutrition in seed propagated potato (Solanum tuberosum L.) plant

Abstract

Potato (Solanum tuberosum) showed a well-established mutualistic association with arbuscular mycorrhizal fungi. In the present study, earthen pots containing autoclaved soil were taken in which surface sterilized potato seeds were sown. The seed sowed earthen pots were inoculated by sterilized spores of arbuscular mycorrhizal fungi along with sterilized inoculated maize-root fragments, while the rest half of the seed filled pots, without any inoculation depicting control but were provided with non-inoculated maize root fragments. The inoculation was performed twice; first inoculation was done 3 days prior to sowing of potato seeds and second at the time of seedling emergence. Sampling of the inoculated as well as of control plants was performed at 20-day intervals till 80?days after tuber initiation. An increment in the level of metabolites as well as mineral nutrient was found in mycorrhizal inoculated potato tubers in contrast to non-inoculated. Our work demonstrates that inoculation has a great potential in enriching storage metabolites and nutrients in potato plant in low yielding soils.