The bulbous vegetable onion Allium cepa Var. aggregatum L. (2n=16) is the most important species of Allium group and is regarded as the single most important vegetable spices as it forms an indispensable part of many diets, both vegetarian and non-vegetarian. Onion is valued for its bulbs having characteristic odour, flavor and pungency. Onion is regarded as a highly export oriented crop and earns a valuable foreign exchange for the country. Weeds are of great menace as they interfere with production of crop and add to the cost of cultivation. The reduction in crop yield has direct correlation with weed competition. Onion exhibits greater susceptibility to weed competition as compared to other crops due to its inherent characteristics such as their slow growth, small stature, shallow roots and lack of dense foliage. The effective weed control involves identification of weed flora, method of weed control and judicious combination of effective weed control methods. Hand weeding in onion is a common practice in India, but it is a tedious, expensive and time consuming task due to closer spacing and shallow root system. Non-availability of labourers during critical period of crop makes hand weeding difficult leading to heavy yield losses. Spraying of pre-emergence herbicides keeps the crop in weed free conditions during the early stages. At later stage, second flush of weeds will affect the bulb formation. Hand weeding helps to keep the weed population below economic threshold level throughout the crop growth period. Pre-emergence combined with hand weeding may be costly because of the reduced labour availability and higher labour cost. After bulb formation manual or mechanical methods of weed control will damage the bulb. Application of early post emergence may be helpful to reduce damage to the bulb, weed competition and cost of weeding. Hence a brief review was presented to find out the effect of different weed management method in onion.

Weed management in onion: A review

<div style="text-align: justify;">India is the second largest producer of onion in the world next after China. Mechanization of farming is increasing day by day to produce yield of crop for gaining the profit. This study was related to the development of an onion bulblet planter for vertisol. The development and fabrication of different furrow opener for matching to the existing inclined plate metering device for planting of onion bulblet. The performance of onion bulblet planter in term of depth and width of planting, missing index percentage, multiple percentage, seed damage , actual field capacity and field efficiency. The result indicated that the field efficiency was maximum 83.33% with minimum seed damage 10.2%. Multiple index was 5.1%, missing index was 2.2 % and bulb to bulb spacing was 10.66 cm in chisel type furrow opener at 1.8 km/h speed with moisture content 17.2 %.&nbsp;</div>

Development and performance evaluation of an onion bulblet planter for vertisol

<div>Background: Onion (Allium cepa L.) is an important and indispensable item of every kitchen. It is used as a vegetable, spice and condiment and commands an extensive internal market. Even though onion is one of the major crops in India, its cultivation is not yet popular in Kerala. Successful onion production depends on the selection of varieties that are adapted to different conditions imposed by specific environment and best planting time. In this background, the current study aimed to evaluate five onion varieties in the tropical planes of Kerala and also to study the effect of different planting time and varieties on the performance of onion in Kerala. 
 
Methods: Five onion varieties were evaluated in four different dates of planting with an interval of fifteen days. Planting commenced from 10th November to 25th December 2017 in a split plot design with four replications. Yield attributing characters such as number of leaves per plant, leaf length, bolting percentage, neck thickness, bulb weight and yield were noted. 
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Result: All the parameters showed a significant variation over different dates of planting. There was a significant variation in number of leaves per plant, leaf length, bolting percentage, total bulb yield and neck thickness among the varieties. Interaction effect of varieties and dates of planting was significant only for leaf length and total bulb yield. Highest bulb weight was recorded in 25th Nov. planting. Highest yield was recorded in 25th Nov. which was on par with 10th Dec. and 10th Nov. plantings. Arka Kalyan recorded a highest yield, which was statistically on par with Agrifound Dark Red and Arka Pragati. Varieties when planted on 25th Dec. recorded a lowest neck thickness. Agrifound White exhibited a non-bolting behavior in all the dates of planting. Overall performance and yield of onion was found to be better when planting was done on 25th November.</div>

<div>Effect of Varieties and Planting Time on the Performance of Onion under Tropical Planes of Kerala</div>

<div>Onion is one of the most important commercial crops in India which is used as a vegetable, spice and rich in medicinal properties. In India major onion producing states are Maharashtra, Karnataka, Madhya Pradesh, Gujrat, Bihar, Andhra Pradesh and Rajasthan. In South India onion is cultivated three times in a year as rabi, kharif and late kharif crop whereas, in North India it is generally cultivated as rabi crop. Major portion (60%) of onion produce comes from rabi season while kharif and late kharif crops contributes to a little extent (40%) in some parts of country. Maharashtra, Gujarat, Karnataka and Rajasthan are major kharif onion producing states. Rabi onion is generally harvested in April-May whereas kharif onion and late kharif is harvested in the month of October-November and January-February, respectively. Major portion of rabi season produce is stored upto October month for domestic consumption. There is a critical gap in supply of onion from the months of October to December. Therefore, kharif onion plays an important role not only in fulfilling consumers demand but also in controlling market price of onion. So far kharif onion production in India is limited to three four states only and it should be prioritized in other states too by keeping in view its importance. Various research perspectives, challenges and management strategies involved in kharif onion production has been reviewed in this article.</div>

Kharif Onion Production in India- Present Status and Future Potential: A Review

<div style="text-align:justify">Background: Seed is an important component and the quality seed plays a crucial role in agricultural production as well as in the national economy. Availability of viable and vigorous seeds at the planting time is important. Onion seeds have a short life span among the vegetable crops and lose viability rapidly after harvest. The main reason for the low quality of onion seeds includes a long flowering period resulting in different stages of seed maturity in the umbel, very fast reduction of viability if stored in suboptimal conditions and seed infestation with fungi. Seed priming is a widely used technique to enhance seed performance during storage. 
 
Methods: The seed was primed with Neem leaf powder (100 g/kg) after hydration and dehydration, hydration with KH2PO4 (2.0%), KNO3 (1.0%), K2SO4 (1.0%) and Captan (N-trichloromethylthio-4-cyclohexane-1,2-dicarboximide) at 2.5 g/kg and stored in polyethylene (100&micro;) bags under ambient conditions. After each treatment, seeds were dried back to their original moisture content under shade.&nbsp;&nbsp; 
 
Result: The results revealed that different priming treatments had a significant effect on germination percentage, seedling length and vigour index-I except for moisture percentage in both the years. The maximum germination (74.1 and 71.2%) was observed in seeds treated with Captan (2.5 g/kg) followed by Neem leaf powder 100 g/kg seed (71.1 and 69.72%) during 2014-15 and 2015-16, respectively. The onion seeds primed with KH2PO4 (2.0%), KNO3 (1.0%) and K2SO4 (1.0%) had an adverse effect on seed germination. The germination decreased significantly with the increase in the storage period. The maximum seedling emergence (60.0%) was observed from the seed primed with Captan (2.5 g/kg) followed by Neem leaf powder 100 g/kg seed (56.1%).&nbsp;</div>

Maintaining Onion Seed Quality during Storage Through Seed Priming

<div style="text-align: justify;">To investigate the effect of planting methods and irrigation levels on irrigation water productivity and onion (Allium cepa L.) yield, a field experiment was conducted on sandy loam soil at the Research Farm of Department of Soil Science, Punjab Agricultural University, Ludhiana during rabi 2011-12. Three planting methods tested include drip irrigated beds, furrow irrigated beds and flat flood irrigation. In drip irrigated beds and furrow irrigated beds three onion rows were planted on 55 cm wide beds at a spacing of 15 cm from row to row. Three levels of irrigation water were tested i.e. IW/PAN-E ratio of 0.3, 0.4 and 0.5 in drip irrigated onions and 1.2, 1.6 and 2.0 in both bed furrow and flat flood methods of irrigation. The results of the experiment indicated that in drip irrigated beds by applying same quantity and 50 per cent of water as of flat flood irrigation, the yield was increased by 43 and 25 per cent, respectively. Irrespective of irrigation levels, highest onion yield (32.5 t ha-1) was recorded under drip irrigated beds followed by furrow irrigated beds (28.5 t ha-1) and least under flat flood irrigation method (25.0 t ha-1). The onion yield increases with the increase in irrigation level in all the planting methods. The highest irrigation water productivity was observed under drip irrigated beds (1.26 t ha-1 cm) followed by furrow irrigated beds (0.84 t ha-1 cm) and least under flat flood irrigation (0.48 t ha-1 cm) with equivalent IW/PAN-E ratios. Bigger size onions (40 mm and 50 mm) were observed under drip irrigated beds followed by furrow irrigated beds and smallest size bulbs under flat flood method of irrigation. The results revealed that drip irrigation could successfully be used for onion production with significant water saving and higher production. &nbsp;</div>

Effect of planting methods and irrigation levels on water productivity of onion (Allium cepa L.)

<div>Background: Maharashtra ranks first in onion (Allium cepa L.) production with a share of 28.32%. However, the productivity of onion is low as compared to other countries. In order to enhance onion productivity, new and innovative agri-inputs are being tried continuously like providing humic acid, fulvic acid, plant growth regulators (PGR), auxin/amino acid spray, seaweed extract, biofertilizers, sulphur application etc. PGRs are considered to be one of the novel inputs that can help in increasing the productivity of onion in India economically. Plant growth regulators are considered as a new generation of agrochemicals when added in small amounts, modify the growth of the plants usually by stimulation or modifying one part of natural growth regulatory system, thereby increasing the crop yield. Most of the research data available is based on biochemical, seaweeds etc. Almost negligible literature is available pertaining to a PGR made with formulation of Seaweed extract and Protein Hydrolysate. An attempt has been made in this research work to evaluate the effect of PGR formulated with seaweed extract and Protein Hydrolysate as major constituents on onion bulb yield through both foliar and drenching application. 
 
Methods: A field experiment for evaluating the effect of plant growth regulator (PGR) formulated by Research and Development Department, M/s Rashtriya Chemicals and Fertilizers Limited was conducted at Chilli and Vegetable Research Farm, Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola (MH). During the experiment, the effect of different concentration of PGR viz., 0.2%, 0.4%, 0.6% and 0.8% and 1.0%, 1.2%, 1.4% and 1.6% through foliar and drenching application, respectively were studied. 
 
Result: Statistically, significant results of plant growth regulator application on vegetative growth, yield and qualitative characters of onion crop were observed. Significantly, maximum bulb yield was observed in the treatment PGR @ 0.6% (255.41 kg/ha) through foliar application which is at par with the treatment PGR @ 1.4% (246.67 kg/ha) through soil drenching along with RDF. According to the results, the suitable PGR dose for studied characters of onion under prevailing conditions was 0.6% foliar spray and 1.4% soil drenching along with recommended dose of fertilizers.</div>

​Response of Plant Growth Regulator on Bulb Yield of Onion (Allium cepa L.)

<div>Background: This study was carried out to determine the effect of addition of 1% dietary garlic and onion powder on the internal and external quality characteristics and chemical and fatty acid composition of Chukar partridges eggs. 
 
Methods: A total of 240 Chukar partridges with 60-week age was assigned to four dietary treatment group: control, 1% onion powder, 1% garlic powder and garlic onion powder, respectively. Totally, 92 eggs obtained from partridges were used for the study. 
 
Result: The addition of onion powder had significant effect on yolk weight (P&lt;0.05). Supplementation of the diets with garlic and onion powder did not significantly affect quality traits of chukar eggs (P&gt;0.05). Moisture, ash and protein contents and 16 fatty acid composition of chukar eggs were not statistically affected by the addition of garlic and onion powder either. In conclusion, the addition of 1% dietary garlic and onion powder did not cause a significant change in the internal and external quality characteristics and fatty acid composition of the Chukar partridge eggs. Increasing the rate of garlic and onion powder to the chukar ration may cause some significant differences on the egg parameters.</div>

Egg Quality Traits, Chemical Analysis and Fatty Acid Composition in Chukar Partridges Supplemented with Garlic and Onion Powder

<div style="text-align: justify;">Onion (Allium cepa L.) is one of the most important bulb crops in India, which plays a major role in supplementing the income of small and marginal farmers of Sikar District in Rajasthan. In the district one of the major constraints in onion cultivation is poor keeping quality of local variety. Most of the farmers in the district are still using the locally self produced seeds of unknown source. The cultivation of recommended /released varieties is very limited. To replace this anomaly Krishi Vigyan Kendra, Fatehpur-Shekhawati, Sikar has introduced improved variety of onion through front line demonstration in selected villages of Sikar district with the objective of getting higher production with good storage potentials under real farm situation. The result showed that maximum TSS (13.1%) and average keeping quality (5-6 months) was recorded in demonstration variety whereas, it was very less in farmers practices. On an average the bulb yield achieved by adopting improved production technology was 347.62q/ha, whereas, the corresponding yield ranges under farmers practices was to 343.20q/ha. The economics of data indicated that an average of Rs. 160834/ha was recorded net profit under recommended practices, while it was Rs 62030/ha under farmer practices. Cost benefit ratio was 2.34 under demonstration, while it was 1.90 under farmer practices. The study suggests that front line demonstration is one of the key extension tools for transfer of technology at grass root level that directly impact the horizontal spread of technology. This can be also a good option for enhancing farmers&rsquo; income.</div>

<div style="text-align: justify;">Impact of front line demonstration on yield and economics of onion</div>

Podzolic soils belong to a low fertile soils. To obtain a crop it is necessary to add fertilizers. It was suggested to use vermicompost as fertilzer. Vermicompost is a natural fertilizer that is beneficial against chemical fertilizers. To confirm positive effect of biohumus different plants were grown. Grass and radishes were grown in forms, and radishes, onion and marigolds were grown in outdoor experimental plot. 
It was grown plants in poor podzolic soil with added vermicompost. Grass had a higher growth in medium with 4 % vermicompost. The best foliage length of radish was for sample with 4 % vermicompost added. Radish root crop diameter was 2.5 times more than control when growing in forms. In experimental plot radishes were grown with 43.5 % increasing in weight and 17.7 % increasing in diameter. Incorporation of vermicompost in amounts of 5 kg/m2 and 7 kg/m2 led to increasing the weight and diameter of onions. The length of onion leaves was slightly larger than control. Marigolds grown in vermicompost medium had the most powerful sprouts and greatest length. Marigolds stem diameter, flower diameter, and quantity of inflorescences were also higher than control. Obtained data indicates the success of using vermicompost for podzolic soils enrichment and plants growing.