Total Bulb Yield Research Articles

Growth and Bulb Yield of Garlic as Influenced by Clove Size.

Garlic is an important cash crop in many regions of Ethiopia. However, the yield of the crop is constrained by several factors. Among these, inappropriate clove size is one of the major agronomic practices that can decrease the yield of the crop. Hence, a field experiment was conducted during the 2020/21 main cropping season at Debre Berhan University, College of Agriculture and Natural Resource Sciences, demonstration and research site to evaluate the effect of clove size on growth and bulb yield of garlic (Allium sativum L.). The treatments consisted of five clove sizes: 1–1.49 g, 1.5–1.99 g, 2–2.50 g, 2.51–2.99 g, and 3–3.5 g. An improved variety “Tseday” was used as a planting material. The experiment was laid out as a randomized complete block design in a factorial arrangement and replicated for three times. The results revealed that clove size significantly influenced all growth and yield parameters of garlic. Planting of 3–3.5 g cloves reduced days to emergence by 11 and 6.33 days and days to maturity by 28.33 and 18.00 days, respectively, as compared to planting of 1–1.49 g and 2–2.5 g cloves. This treatment also increased total bulb yield by 25.88% and 15.58%, respectively, as compared to planting of 1–1.49 g and 2–2.5 g cloves. In addition, this treatment significantly increased most of the growth and bulb yield components. Hence, it can be concluded that planting of 3–3.5 g cloves could be recommended to enhance early emergence, good vegetative growth, and total bulb yield of garlic.

Genetic variability and correlation studies among morphological traits in garlic (Allium sativum L.)

Thirty-four genotypes of garlic were evaluated at Vegetable Research Station of C. S. Azad University of Agriculture and Technology, Kalyanpur, Kanpur during rabi season of 2018-19 to study the genetic variability as well as an association for 18 yield and yield developmental characters. A wide range of variation was observed for most of the characters like total bulb yield, marketable bulb yield, plant height, average weight of bulb, days to maturity, number of cloves bulb-1, average weight of cloves bulb-1, leaf length and dry matter content. The phenotypic coefficient of variation was higher than the genotypic coefficient of variation for all the traits studied, indicating influence of environment in the expression of these traits. Average weight of cloves bulb-1, average weight of bulb and plant height had a high phenotypic and genotypic coefficient of variations coupled with high estimates of heritability and expected genetic advance. The marketable bulb yield had a significant positive correlation with characters viz., total bulb yield, width of cloves, average weight of bulb, number of leaves plant-1, days to maturity and average weight of cloves bulb-1 indicating that selection based on these traits will help to increase the yield of garlic.

Effect of Drip Lateral Spacing and Water Levels on Yield and Water Use Efficiency of Onion ( allium cepa l. ) Under Awash Melkassa Climatic Condition

Water being scarce resources, irrigation water is the most limiting factor for vegetable production in the central rift valley of Ethiopia. Drip irrigation technique together with deficit irrigation application improves crop yield and water use efficiency. Hence, the objective of this study was to enhance onion production and WUE through the application of drip irrigation technology and deficit irrigation application. Field experiment was conducted at Melkassa agricultural research center during the cool cropping season of 2019/2020 to investigate the effects of drip lateral spacing and irrigation levels on onion yield, water use efficiency and net return. Two levels of drip lateral spacing viz., lateral placed in every row and between two rows, and three levels of deficit irrigation viz., 80% ETc, 70% ETc and 55% ETc, and one-full irrigation (100% ETc). The treatments were arranged in split plot with three replications. Data were analyzed using statistical package appropriate to split plot with the help of SAS software. The result showed that onion yield, yield parameters and water use efficiency was affected by the effects of drip lateral spacing and irrigation water levels but not affected by their interaction effect. Onion bulb yield decreased with increased levels of water deficit. In contrast, both water use efficiency and irrigation water use efficiency increased with increase in water deficit level. Maximum onion bulb yield of 41.43 t ha-1 were obtained from lateral spacing in every row and full irrigation application level of 100% ETc and has no a significant difference with every row lateral spacing, and 85% and 70% ETc irrigation application levels. The highest water use efficiency of 13.33 Kgm-3 was recorded from every row drip lateral spacing and irrigation application of 70% ETc. Therefore, onion could be irrigated every row drip lateral spacing with 70% ETc application to increase water use efficiency without a significant total bulb yield reduction.

Evaluation of Different Rates of NPS on Growth and Yield Performances of Garlic (Allium sativum L.) in Cheha District, Gurage Zone, Ethiopia

A field experiment was conducted on 2019 growing season to evaluate effects of different rates of nitrogen, phosphorus, and sulfur on growth and yield of garlic under supplemental irrigation. A local variety, Tuma, was used and treated with six rates of NPS (T1 (0 : 0 : 0 kg/ha NPS) (control), T2 (19 : 38 : 7 kg/ha NPS), T3 (28.5 : 57 : 10.5 kg/ha NPS), T4 (47.5 : 76 : 14 kg/ha NPS), T5 (47.5 : 95 : 17.5 kg/ha NPS), and T6 (57 : 114 : 21 kg/ha NPS)). The experiment was laid out in randomized complete block design and replicated three times. Data were collected for days to 50% emergence, plant height, leaf number, leaf length, bulb weight, and total bulb yield. SAS version 9.2 was used to analyze the data. Means were separated using Fisher’s test at 5% level of significance. All parameters were significantly P < 0.05 affected by the rates of NPS. The early days to 50% emergence (16) was recorded from T6 (57 : 114 : 21 kg/ha NPS), whereas the late days to 50% emergence was recorded from the control treatment (T1). Significantly highest leaf length (41.51 cm), leaf number (13.63), plant height (61.19 cm), bulb weight (39.44 g), and total bulb yield (14.91 ton ha−1) were recorded from T6 (57 : 114 : 21 kg/ha NPS). Therefore, from the result of this study, it can be concluded that the maximum total bulb yield of garlic was obtained with the application of 57 : 114 : 21 kg/ha NPS rate.

Response of Onion( Allium Cepa L, ) to Different Irrigation Levels Under Drip and Convetional Furrow Irrigation With and Without Mulch at Melkassa , Central Rift Valley of Ethiopia

Water is a scarce resource in Central Rift Valley of Ethiopia and is a major limiting factor for crop production. Onion is one of the major economically important vegetable crops grown under irrigation in central rift valley. The field experiment was conducted at Melkasa agricultural research center during the dry season to identify irrigation method and irrigation application level with and without mulch that maximizes productivity of onion per unit of water consumed and enhanced onion crop production. The experiment was carried out using split plot design inRCBD having twelve treatments with three replications.The FAO’s recommended allowable Manageable depletion level of onion is 100%. In this study 75%, 100% recommended and 125% were tested. The experiment consisted of two irrigation methods viz.,furrow irrigation and drip irrigation as main plot and three levels of Manageable allowable depletion viz., 125%, 100% and 75% with and without mulch as sub-plot.The analysis of variance revealed that irrigation methods and management allowed depletion levels had a significant and p<0.05) effect on onion vegetative parameters like plant height, leaf height and yield parameters like bulb diameter, bulb height, total bulb yield, marketable bulb yield, and water productivity. The highest and lowest onion vegetative and yield parameters were obtained from drip irrigation and furrow irrigation method, respectively. Moreover, the highest and lowest onion vegetative and yield parameters were obtained from drip irrigation under 75% MAD with mulch and furrow irrigation under125% MAD without mulch, respectively. Further, their interaction had a significant effect on total bulb yield and water productivity. The maximum total bulb yield (37.1 ton/ha), marketable bulb yield (33.1 ton/ha), bulb diameter (5.6 cm), crop water use efficiency (0.78 kg/m 3 )and irrigation water use efficiency, (0.60 kg/m 3 ) were observed from drip irrigation method at 75% MAD with mulch application, while significantly lower as (30.5 ton/ha), (26.7 ton/ha), (5.0 cm), (0.53 kg/m 3 )and (0.40 kg/m 3 ) respectively were recorded from furrow irrigation method at 125% MAD with out mulch application. Generally, drip irrigation was working efficiently according to its design and economically acceptable. Among all tested treatments drip irrigation method under 75% MAD with mulch was the best practice because of its high yield and water productivity . Keywords : Drip irrigation, Furrow irrigation, MAD, Onion, Water Use Efficiency DOI: 10.7176/JNSR/12-15-02 Publication date: August 31 st 2021

Seasonal plant growth, leaf and bulb mineral nutrients, and bulb yield and quality under chemical, mixed, and organic fertilization in sweet onion (Allium cepa L.)

The utilization of organic fertilizers is of growing interest to improve soil quality and increase environmental sustainability. There is, however, limited information on the use of organic fertilizers for sweet onion production. The objective of this study was to evaluate the effects of chemical, mixed, and organic fertilizers on plant growth, bulb yield and quality, and mineral nutrients of sweet onion. The study was conducted at the Horticulture Farm, Tifton Campus, University of Georgia, in the winters of 2013, 2014 and 2017. The experimental design was a randomized complete block with three fertilizer treatments and four replications. Fertilizer treatments consisted on the application of Chemical (100% N), Mixed [chemical (50% N) + organic (50% N)] and Organic (100% N) fertilizers. In all treatments, the crop received a total of 150 kg·ha−1 N. Plants in the Organic treatment showed augmented root growth and decreased leaf nitrogen compared to the Chemical and Mixed treatments. There were no differences in mean seasonal shoot and bulb dry weights and root-to-shoot ratio among treatments. Fertilizer treatments also had no impact on marketable and total bulb yields, bulb concentrations of macro and micronutrients, bulb disorders and diseases, and bulb chemical composition. Shoot and root growth increased with increasing air temperature, which explains the reduced plant growth during the winter. In conclusion, sweet onion grown with organic fertilizer alone or mixed (50% organic N + 50% inorganic N) produced plants and bulb yields and quality comparable to those grown with chemical fertilizer.

Quantification of water stress impacts on canopy traits, yield, quality and water productivity of onion (Allium cepa L.) cultivars in a shallow basaltic soil of water scarce zone

Understanding and mitigating the adverse impacts of water stress on agriculture production have become global concern in water scarce environments. Particularly, Deccan plateau, the largest semi-arid zone of peninsular India, is confronted with severe water resources conflicts and extensive pressure for food production under climate change scenario. For sustainable agriculture, it is critical to quantify the impact of water stress on major crops like winter onion (Allium cepa L.) which is grown under diverse water management practices on shallow basaltic soils of this region. We conducted a field experiment during two growing seasons (2017–18 and 2018–19) for evaluating responses of different cultivars of red (B. Raj, B. Kiran, B. Super, B. Red and Local-Fursangi) and white (B. Shubra, B. Sweta and B. Safed) onion to variable water stress created using a line source sprinkler (LSS) system. There was a 1.1, 1.6, 3.9, 9.2 fold decline in total bulb yields (TBY) with increasing water deficit i.e. when depth of irrigation water (IW) applied equalled 0.60, 0.40, 0.20 and 0.00 times the cumulative open pan evaporation (CPE) as compared with the recommended practice (IW:CPE 0.80). The TBY increased between 86.2 and 106.6 Mg ha−1 in red cultivars when irrigation was scheduled at excess to optimum water regimes (IW: CPE 0.80–1.00), while it was improved by 5.0–20.4% for white cultivars under medium (0.40–0.59) to severe (0.0–0.39) water deficit stress. Further, highest (4.3–16.2%) improvement in TBY of Local cultivar was reported irrespective to different water stress levels. Local and white cultivars could have better tolerance to water stress by keeping cooler canopy temperatures, higher leaf relative water content and modulating the stomatal opening. Lower yield losses due to rotting (0.30–1.81%) and splitting (4.4–6.5%) of bulbs were observed in red and white cultivars. This study further endorses the appropriate selection of onion cultivars reduces water requirements by 37.5–61% to attain similar water productivity (16.0 kg m−3) as with recommended irrigation level. Increased in water stress levels though reduced quality of physical traits of harvested bulbs viz., mean weight, average dia., shape index (SI), harvest index (HI) and firmness, these improved the storage quality. Water deficit also increased accumulation of soluble solids, total phenolics, protein, dry matter and elevated the pH and rehydration quality besides potentially affecting the enzymatic activity (SOD and POD) of onion cultivars. It was concluded that white onion cultivars like B. Shubra with higher WP under medium and severe water deficit stress and ‘Local’ red cultivar should be preferred for efficient utilisation of water resources both in terms of the productivity and post-harvest quality of onion under drought prone and shallow basaltic regions of Deccan plateau.

Effect of Varieties and Planting Time on the Performance of Onion under Tropical Planes of Kerala

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. 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.

Evaluation of True Seed Shallot Varieties for Yield and Yield Components

Shallot (Allium cepa var. ascalonicum Backer) is an important vegetable crop cultivated by smallholder farmers for consumption and income generation in Ethiopia. However, scarcity of high yielding varieties as well as lack of superior planting material seriously constrains productivity of the crop. Research project was initiated aiming at studying adaption of true seed shallot for yield and components. A series of experiments were conducted using the randomized complete block design to identify the appropriate variety for production of bulb yield. The combined analysis of variance results for marketable bulb yield (kg/plot), unmarketable bulb yield (kg/ha), total bulb yield (kg/plot) and total bulb yield (t/ha). The results showed that the mean squares for main factors of genotype and year as well as interaction of genotypes x year were significant for marketable bulb yield (kg/plot). The overall marketable yield range of the shallot varieties was from 256.56- 171.49qtha^-1 and the average number of splits per plants ranged from 8- 4.72. Improved Minjar shallot variety showed its superiority in marketable bulb yield (kg/plot), total bulb yield (kg/plot) and total bulb yield (t/ha) yields as compared to other varieties. Therefore, as there was no significant yield advantage between these varieties from true seed study area, so the experiment could be repeated across locations to come up with good conclusion for recommendation.

Performance and Adaptability Evaluation of Improved Onion Varieties (<i>Allium cepa</i> L.) for Bulb Yield and Some Agronomic Traits

Onion is one of the most important vegetable crops in the world including Ethiopia. The field experiment was conducted in Arsi zone at Kulumsa Agriculture Research Center and Ziway Dugda districts under irrigation condition. A total of five improved onion varieties were evaluated in Randomized Complete Block Design with three replications with the objectives of studying the performance and adaptability of improved onion varieties for bulb yield and yield related traits in 2017 during off season. The combined Analysis of variance (variety by location) revealed that significant difference between improved onion varieties for maturity date, marketable and unmarketable bulb yield tons per hectare, bulb length in centimeter, and bulb weight in gram was observed. But non-significant difference for plant height in centimeter, total bulb yield tons per hectare and average bulb diameter in centimeter were observed between improved onion varieties. Except variety Adama Red all the tested improved onion varieties (Melkam, Nafis, Nasik Red and Bombay Red) was well performed and adapted. These varieties were gave more than 40 marketable bulb yield t ha^-1. So those improved onion varieties were recommended for the study area and areas of similar agro- ecological zones under off season growing condition.

The Effect of Phosphorus and Transplanting Date on Growth, Yield and Yield Components of Onion (Allium Cepa L.) Under Irrigated Conditions at Adami Tulu Jedo Kombolcha Woreda, Oromia Region

A field experiment was showed to decide the influence of transplanting date and phosphorus level on growth, yield and yield component of onion at Adami Tulu Jedo Kombolcha Woreda during 2017/18 season. The treatments comprised of three transplanting date (42, 49 and 56 days of transplanting date) and phosphorus levels (0, 23, 46, and 69 kg P 2 O 5 ha -1 ). The experiment was laid out in RCBD with four replications. In this study, transplanting at 56 days of transplanting date fertilized with 69 kg P 2 O 5 ha -1 recorded the highest total bulb yield and marketable bulb yield, but no significant difference was showed with that obtained at 46 kg P 2 O 5 ha -1 with the same transplanting date. The economic analysis revealed that the highest net benefit with low cost of production was obtained in response to the application of 46 kg ha -1 and the transplanting age of 56 days. Keywords: bulb yield, Onion, economic analysis, phosphorus, transplanting date. DOI: 10.7176/JBAH/11-1-03 Publication date: January 31 st 2021

Efficiency of pendimethalin, ioxynil, and accase inhibitors in controlling weeds in direct seeding onion

This study evaluates whether the initial application of pendimethalin can increase the efficiency of ioxynil and ACCase inhibitor treatments in controlling weeds in direct seeding onion. The experiment was carried out in a commercial field in Ituporanga city, Santa Catarina State, Brazil. The onion cultivar Bola Precoce was used. The experimental design was in randomized blocks, in a factorial scheme (2 x 3) + 1, with four replications. Treat­ments consisted of pendimethalin application in the initial stage (0 or 600 g ha -1 ), three treatments based on ioxynil and ACCase inhibitors, sprayed at postemergence (ioxynil + clethodim (formulated as Select ® ); ioxynil + fluazifop; and ioxynil + clethodim (formulated as Poquer ® )), and a weeded control. Pendimethalin was sprayed immediately after onion crop establishment, and postemergence treatments were sprayed when the onion had 3 and 4 leaves (two sequential applications). The following were evaluated: control of Lolium multiflorum , Corono­pus didymus , and Galinsoga parviflora , plant stand, bulb diameter, bulb weight, and total bulb yield. All treatments reached 100% control of L. multiflorum . All treatments were ineffective in controlling C. didymus and G. parviflora ; however, the control of these weeds increased after pendimethalin application. The chemical treatments tested did not negatively influence any of the studied onion crop variables. There was a significant difference only for pendimethalin application in the initial stage, which significantly favored the variables under study. Pendimethalin application in the initial onion stage improved weed control and helped in maintaining bulb yield in direct seeding onion.

Study on effect of soil and foliar application of silicon on growth, yield and quality on kharif onion (allium cepa l.)

The field experiment entitled “Effect of soil and foliar application of silicon on soil nutrient availability, uptake, yield and quality of kharif onion” was conducted during Kharif 2016 – 2017 at Post Graduate Institute research farm, Mahatma Phule Krishi Vidyapeeth, Rahuri with a view to study the effect of levels of silicon on growth, yield, and quality of kharif onion.The investigation was carried out in Randomized Block Design (RBD), fourteen treatments combinations comprised of soil application of three levels of calcium silicate (50, 100 and 150 kg Si ha-1) and three concentration of silicic acid (SA) 1, 2, and 3 ppm through foliar spray. Two treatments absolute control and GRDF were taken for comparison having 0 kg Si ha-1. The neck thickness, equatorial diameter, polar diameter and, total yield of bulbs and straw yield of onion were recorded. The chemical properties viz. pH, EC and OC showed significantly influenced due to application of silicon. In case of treatment T14 recorded significantly superior pH, EC and OC (8.35, 0.54 and 0.60 % respectively). The treatment T14 recorded significantly highest polar diameter (5.55cm), equatorial diameter (5.94cm), neck thickness ( 0.88 cm) highest weight per bulb (83.50 g), bulb yield (37.50 t ha-1) and straw yield (2.40 q ha-1) respectively. It is concluded that treatment (T14) was found beneficial for maintaining soil fertility, for enhance crop growth and for increase yield and yield contributing character of onion on shallow soil.

Regulated Deficit Irrigation and Onion (Allium cepa L.) Yield Response on Water Productivity

Irrigation is the only solution to improve crop production and productivity thereby contributing towards food security, self-sufficiency and export market. The efficient use of water by irrigation system is becoming increasingly important in arid and semi-arid regions with limited water resources. The Experiment was conducted in Debre Zeit Agricultural Research Center with the Regulated Deficit Irrigation and Onion (Allium cepa L.) Yield Response on Water Productivity in Ethiopia during 2017/2018 cropping season. The objective of the experiment was identify the pin point of water stress threshold value of onion under deficit irrigation and investigate the effect of alternate, fixed and conventional furrow irrigation methods on crop yield and water productivity under deficit irrigation. The experimental treatments had three furrow irrigation methods, (alternate furrow irrigation (AFI), fixed furrow irrigation (FFI) and conventional furrow irrigation (CFI)) and two deficit irrigation levels of application, viz., 85 % ETc, and70 % ETc and a control irrigation of 100%ETc. The design of the experimental plot was split plot in RCBD arrangement and replicated three times. The three furrow irrigation methods were arranged as main plots and the deficit levels as sub plots a total of nine (9) treatment combinations. All collected data, were statistically analyzed using SAS 9.1 statistical software. The experimental study result showed that bulb diameter, unmarketable bulb yield and total bulb yield of onion were highly significance difference (p<0.001) both in furrow irrigation methods and irrigation levels. Likewise diameter of onion also gave highest on CFI and 100%ETc irrigation water application level which is 6.69cm and 6.94cm respectively. According to the results obtained, the highest total yield was recorded for the treatment of 100%ETc irrigation water application and AFI of the furrow irrigation method 38947kgha -1 and 35920kgha -1 respectively however, the lowest total bulb yield of 30253kg ha -1 and 29135kg ha -1 were recorded when FFI system was applied and in 70%ETc of water applied. Bulb height of onion was highly significance difference (p<0.001) only on deficit irrigation levels. On the other hand, marketable bulb yield, irrigation water use efficiency and crop water use efficiency were significance difference (P ≤ 0.05) by the interaction of furrow irrigation methods and deficit irrigation levels. The highest average marketable bulb yield of onion was obtained 42219kgha -1 on CFI with the combination of 100%ETc irrigation level in addition to this IWUE and CWUE both are recorded highest result on 70%ETc and AFI furrow irrigation method. Generally, among all irrigation treatments 70%ETc deficit irrigation level applied under AFI method was efficient in conserving significant irrigation water. Therefore, it could be concluded that, AFI can save a substantial amount of water and labor without highly reduction of onion yield and the lowest CWUE and IWUE was gave FFI followed by CFI. Keywords: Alternate furrow irrigation, Conventional furrow irrigation, Deficit irrigation, fixed furrow irrigation, Onion DOI: 10.7176/JRDM/71-02 Publication date: November 30 th 2020

Cut-off irrigation as an effective tool to increase water-use efficiency, enhance productivity, quality and storability of some onion cultivars

Water management is becoming commonplace in discussions of high-yield farming and modern agricultural best practices. A field experiment undertaken in the Northern region of Egypt, Kafr El-Sheikh Governorate, with four cut-off furrow irrigation treatments (100%, full irrigation – considered as a control; 90%, 80% and 70% of strip length) was used to compare the effects of reduced water supply on onion (Allium cepa, L.) production via assessing three different cultivars (e.g., Giza red, Giza 20 and Behairy red). A strip-plot design with three replicates was employed in this regard during two successive seasons (2014–2015/2015–2016). Regardless of onion type, water supply at 80% level resulted in higher marketable and total bulb yield (t/ha) with improved quality traits and storability compared to other irrigation treatments. There have been few significant interspecies differences. The most notable significant differences were recorded in Giza red and Behairy red for all studied characteristics. The highest results were reached with Giza red under the use of 80% irrigation level. In addition to the excellence in improving the overall quality and harvestable yield, this treatment (80% watering) has produced relatively good results with respect to the consumptive water-use efficiency, water productivity and showed significant benefits in terms of saving irrigation water. Maximum water saving was obtained under the use of 70% irrigation treatment, but in the absence of a good and economically unacceptable yield. The traditional technique (100% water supply) consumed much water, surpassing the most effective treatment (80%) by 1195.77 cubic meter per hectare (i.e., 11.96 cm in depth/height). In conclusion, cut-off irrigation technique is considered an efficient and effective intervention approach for onion yield increases while maintaining post-harvesting quality and water savings. However, extending the study beyond onion is critical to increase the range of benefit with regard to other crops, as well for adequate management of water under deficit irrigation conditions.

ADAPTIVE PERFORMANCE OF GARLIC VARIETIES UNDER HIGH GANGES RIVER FLOODPLAIN SOIL (CALCAREOUS) OF BANGLADESH

Any variety needs to evaluate at different locations, along with variable soils for asses their yield potentiality after its releasing. Thus, an experiment was conducted at Multi Location Testing (MLT) site, Kushtia Sadar Upazila, under High Ganges River Floodplain (AEZ-11) in Bangladesh, during three consecutive Rabi seasons of 2013-2014 to 2015-2016. The objective of this study was to evaluate the performances of garlic varieties and economic profitability of these varieties at farmer’s field. There were three garlic varieties, namely BARI Rashun-1, BARI Rashun-2 and a local cultivar, which were evaluated at six dispersed locations as replications. Results observed that the highest yield (8.34-9.80 t ha-1) was obtained from BARI Rashun-1, which was followed by BARI Rashun-2 (7.43-9.48 t ha-1) and the local one (7.12-9.15 t ha-1). BARI Rashun-1 produced 3-12% higher yield over BARI Rashun-2 and 7-20% over the local cultivar, respectively in three consecutive years. Correlation analysis showed that there were positive and significant correlation among bulb yields with bulb length and individual bulb weight. Regarding the functional relationship, the traits like crop duration, plant population, plant height, bulb length, bulb width, individual bulb weight had positive contribution on the bulb yield. It was dependent on those traits, and accounted for 12, 36, 0.05, 45, 41 and 55% of the total bulb yield variation, respectively. The highest gross return (Tk. 3, 63,700 ha-1) and gross margin (Tk. 2,19,425 ha-1) were obtained from BARI Rashun-1. As such, this variety performed as the best, in respect of higher bulb yield potential, as well as the highest economic return among the tested varieties, which was followed by BARI Rashun-2. Therefore, the result of this study could be helpful for improving bulb production of garlic under High Ganges River Floodplain soil (calcareous soils) in Bangladesh.

Growth and yield of onion (Allium cepa L.) as affected by farmyard manure and nitrogen fertilizer application in Tahtay Koraro District, Northwestern Zone of Tigray, Ethiopia

A field experiment was carried out in Tahtay Koraro district of Northwestern zone of Tigray from October 2017 to April 2018, to assess the effect of organic and inorganic fertilizer on growth, yield and yield components of onion. The experiment consisted of four levels of FYM (Farmyard manure) as 0, 10, 20 and 30 t ha−1 and four levels of inorganic N as 0, 34.5, 69 and 103.5 kg ha−1 factorially arranged in RCB design with three replications. Analysis of variance revealed that the main effect of N, FYM as well as their interactions significantly (P < 0.05) influenced days to maturity, plant height, leaf number, leaf diameter, bulb diameter, neck diameter, average bulb weight, above ground dry biomass, marketable bulb yield and total bulb yield of onion. Similarly, main effects of N and FYM significantly (P < 0.05) affected leaf length, bulb length, unmarketable bulb yield and harvest index. The highest marketable bulb yield of 35.93 t ha−1 and 34.72 t ha−1 were obtained at combinations of 103.5 kg N ha−1 + 30 t FYM ha−1 and 103.5 kg N ha−1 + 20 t FYM ha−1 respectively. However, the lowest marketable bulb yield of 13.88 t ha−1 was obtained from the unfertilized plot. Moreover, the highest marginal rate of return was obtained at combined application of 103.5 kg N ha−1 and 10 t FYM ha−1 and thus can be recommended for onion production in the study area.

Maximizing growth and productivity of onion (Allium cepa L.) by Spirulina platensis extract and nitrogen-fixing endophyte Pseudomonas stutzeri.

The study focuses on the impact of foliar spraying cyanobacterium Spirulina platensis extract and the inoculation with the endophyte N2-fixing Pseudomonas stutzeri, and their mixture in the presence of different nitrogen doses on growth and yield of onion under field conditions. Bioactive compounds of Spirulina and Pseudomonas were analyzed by GC-MC and amino acid production of Spirulina by the amino acid analyzer. Hydrogen cyanide (HCN), indole acetic acid (IAA), ammonia (NH3), pectinase activity, and N2-fixation of Pseudomonas were measured. Plant height (cm), leaf length (cm), number of green leaves, bulb diameter (cm), fresh and dry weight of plant (g), chlorophyll a, b of leaves, bulb weight (g), marketable bulb yield (t. ha-1), cull bulb weight (t. ha-1), total bulb yield (t. ha-1), bulb diameter (cm), total soluble solids (TSS%), dry matter content (DM%), evaluation of storage behavior, and economic feasibility were estimated. Spirulina extract has several bioactive compounds. Pseudomonas can produce HCN, NH3, IAA, pectinase, and nitrogen fixation. The application of mixture with recommended dose of nitrogen increases the onion plant parameters, marketable yield, total bulb yield, bulb weight, bulb diameter, TSS%, DM%, net return, benefit-cost ratio (B:C), lowest cumulative weight loss% of bulbs during storage, and reduce culls weight compared with other treatments in two seasons. Application of S. platensis extract and inoculation with endophyte nitrogen-fixing P. stutzeri enhance the growth and productivity of the onion under different doses of nitrogen fertilizer.

Assessment of Genetic Divergence in Long Day Onion (Allium cepa L.) through Principal Component and Single Linkage Cluster Analysis

To assess the nature and magnitude of genetic diversity in long day onion germplasm by using the principal component analysis and single linkage cluster analysis an experiment was carried out with 34 onion genotypes. High coefficient of variation with wide range in traits indicated an appreciable variability in germplasm. Genotypes were classified into seven principal components having Eigen value &gt; 1, cumulatively accounted for 83.87% of total variability. Principal Component - I contributed for 24.73% of total variation for followed by principal component-II (15.27%). PC-I had high positive loading for bulb weight (0.401), marketable yield (0.338), total bulb yield (0.401) and PC-II had high positive loading for plant height (0.412), PC-III for high T.S.S. (0.276) PC -IV for A grade bulbs (0.436), PC-V for polar diameter of bulbs (0.514), PC-IV negatively loaded with purple blotch (-0.461) and PC-VII for narrow neck thickness (-0 .515). Plotting PC-I aganist PC-II differenciated CITH-O-13, CITH-O-4, CITH-O-22, CITH-O-19, CITH-O-9, CITH-O-6 and CITH-O2 as most divergent genotype.On the basis of single linkage cluster means cluster-I was most importent for average bulb weight, minimum bolters, high marketble bulb percentage high marketable and total bulb yield whereas cluster -II was important for maximum nuber of leaves/plant and minimum neck thicknes. Highest inter-cluster distance was observed between cluter II and Cluster-I(873.5% ).Most divergent genotypes with high inter cluter distance could be the most appropriate parents for crop impovement in onion.

Assessment of Genetic Divergence in Long Day Onion (Allium cepa L.) through Principal Component and Single Linkage Cluster Analysis

To assess the nature and magnitude of genetic diversity in long day onion germplasm by using the principal component analysis and single linkage cluster analysis an experiment was carried out with 34 onion genotypes. High coefficient of variation with wide range in traits indicated an appreciable variability in germplasm. Genotypes were classified into seven principal components having Eigen value &gt; 1, cumulatively accounted for 83.87% of total variability. Principal Component - I contributed for 24.73% of total variation for followed by principal component-II (15.27%). PC-I had high positive loading for bulb weight (0.401), marketable yield (0.338), total bulb yield (0.401) and PC-II had high positive loading for plant height (0.412), PC-III for high T.S.S. (0.276) PC -IV for A grade bulbs (0.436), PC-V for polar diameter of bulbs (0.514), PC-IV negatively loaded with purple blotch (-0.461) and PC-VII for narrow neck thickness (-0 .515). Plotting PC-I aganist PC-II differenciated CITH-O-13, CITH-O-4, CITH-O-22, CITH-O-19, CITH-O-9, CITH-O-6 and CITH-O2 as most divergent genotype.On the basis of single linkage cluster means cluster-I was most importent for average bulb weight, minimum bolters, high marketble bulb percentage high marketable and total bulb yield whereas cluster -II was important for maximum nuber of leaves/plant and minimum neck thicknes. Highest inter-cluster distance was observed between cluter II and Cluster-I(873.5% ).Most divergent genotypes with high inter cluter distance could be the most appropriate parents for crop impovement in onion.