Environmental and genotypic effects on bulb development in onion – a review     

Khalid Mahmud Khokhar 《The Journal of Horticultural Science and Biotechnology》2017,92(5):448-454

Environmental and genetic factors influence growth and bulb development of onions by affecting their physiology. Photoperiod plays critical a role in bulb development and determines the suitability of a cultivar for a particular region. Long days and high temperatures promote onion bulbing. Bulbing is regulated more by temperature than photoperiod, as determined by growing degree days. Far-red light promotes bulbing most effectively. High-temperature storage of sets (above 20–25°C) results in increased total bulb yields, while very high temperature (25.5–31°C) or temperature below 0°C depresses yield. Plant density has an impact on bulb size: the higher the plant density the smaller the bulb size. Onion is more sensitive to water stress during bulb formation and enlargement than during the vegetative stage. Nitrogen improves bulb development, but too much nitrogen promotes excessive vegetative growth and delays maturity. Growth hormones (gibberellins and ethrel) promote the growth and development of bulbs. Flowering and bulb formation in onion is regulated by different (Flowering Locus T) FT genes. Two antagonistic FT-like genes regulate bulb formation. AcFT1 promotes bulb formation, while AcFT4 prevents AcFT1 up-regulation and inhibits bulbing. There is a need to link our research with the genetics and physiology of onions, to enhance bulb yield.  相似文献   

Effect of set-size and storage temperature on bolting,bulbing and seed yield in two onion cultivars     

Khalid Mahmud Khokhar 《Scientia Horticulturae》2009

The effects of three set-sizes (12.5, 17.5 and 22.5 mm in diameter) and seven storage temperatures (0, 5, 10, 15, 20, 25 and 30 °C) on bolting, bulbing and seed yield in two onion (Allium cepa L.) cultivars ‘Hygro’ and ‘Delta’ were investigated. The incidence of bolting increased linearly with set-size and curvi-linearly with decreasing storage temperature. Time to inflorescence emergence and floret opening showed a curvi-linear response to storage temperature with the earliest inflorescence emergence and floret opening occurring at 5 °C and the latest at 30 °C for ‘Hygro’ and at 25 °C for ‘Delta’. Seed yield per umbel also showed a curvi-linear response to storage temperature with the lowest seed yield occurring at 30 °C for ‘Hygro’ and at 25 °C for ‘Delta’ and the highest seed yield at 5 °C. For a seed crop, storage of large sets (22.5 mm) of these cultivars at 5 °C for 120 days appeared to be optimum with 5–12% higher seed yield per umbel than that of 90 days storage. Bulb yield showed a curvi-linear response to storage temperature with the highest bulb yield occurring at 25 °C and the lowest at 5 °C.  相似文献   

Improved survival of rohu, Labeo rohita (Hamilton-Buchanan) and silver carp, Hypophthalmichthys molitrix (Valenciennes) fingerlings using low-dose quinaldine and benzocaine during transport     

Mahmud Hasan  & Amrit N Bart 《Aquaculture Research》2007,38(1):50-58

The effects of fingerlings immersion in low‐dose benzocaine (15 and 30 mg L⁻¹, silver carp and rohu) and quinaldine (100 μL L⁻¹ silver crap and 250 μL L⁻¹ rohu) for 1, 3 and 6 h on stress responses and survival of rohu, Labeo rohita and silver carp, Hypophthalmichthys molitrix fingerlings were evaluated in a transport simulation experiment. Both quinaldine and benzocaine showed low mortalities (0–2%). The total mortality in control (with no anaesthesia) was 30% for rohu and 14% for silver carp. Quinaldine and benzocaine‐treated fingerlings had significantly higher plasma chloride levels than the control in both species. Benzocaine, quinaldine, as well as the control, had an initial elevation of plasma cortisol levels. Benzocaine lost its effectiveness after 3 h exposure while quinaldine persisted throughout the 6 h experimental period. Both sedatives reduced bacterial build‐up compared with the control. No post‐exposure mortality was observed for any of the transport methods assessed 48 h after the treatment. This study suggests that the use of low‐dose benzocaine or quinaldine during transport has positive effect on the survival and health of rohu and silver carp fingerlings.  相似文献   

Comparative mapping and discovery of segregation distortion and linkage disequilibrium across the known fragrance chromosomal regions in a rice F2 population     

Farahnaz Sadat Golestan Hashemi  Mohd Y. Rafii  Mohd Razi Ismail  Mahmud Tengku Muda Mohamed  Harun A. Rahim  Mohamad Abd Latif  Farzad Aslani 《Euphytica》2015,204(3):557-569

  相似文献   

The Contribution of Small-Scale Forestry-Based Enterprises to the Rural Economy in the Developing World: The Case of the Informal Carpentry Sector, Sudan     

Yahia Omar Adam  Davide Pettenella 《Small-Scale Forestry》2013,12(3):461-474

Small-scale forestry-based enterprises connected with wood processing are becoming of growing importance in the rural economy of developing countries. Little attention has been paid to the characteristics of these enterprises and their role in supporting economic development. The objectives of this study are to: (1) determine the socioeconomic characteristics of the operators of these enterprises; (2) assess the contribution of the informal carpentry sector to operators’ income; and (3) identify the factors limiting the expansion of the sector. The study was carried out in the Singa district, Sinnar State in 2011. Snowball sampling was used to select 250 operators from five markets in the district. The quantitative and qualitative data were collected using Participatory Rural Appraisal methods. The results revealed that most operators involved in the informal carpentry sector are males aged <30 years and their businesses have been in existence for <10 years. Operators’ incomes ranged between USD 100 and 500 monthly on average. The results also indicated that the operators face many constraints (e.g. finance shortage, lack of raw materials, insecure market, lack of technology and lack of organization) to expanding the informal carpentry sector. The study concluded that the informal carpentry sector has potential to contribute to rural economic development through increasing income and reducing rural poverty.  相似文献   

Identification and quantification of betalains from the fruits of 10 mexican prickly pear cultivars by high-performance liquid chromatography and electrospray ionization mass spectrometry     

Castellanos-Santiago E  Yahia EM 《Journal of agricultural and food chemistry》2008,56(14):5758-5764

Qualitative and quantitative analyses of betalain pigments in 10 cultivars/lines of prickly pear (Opuntia spp.) fruit grown in Mexico were conducted with reverse phase high-performance liquid chromatography-diode array detection (HPLC-DAD) coupled with electrospray mass spectrometry (ESI-MS). Betacyanins and betaxanthins were identified by comparison with the UV/vis and mass spectrometric characteristics as well as the retention times of semisynthesized reference betaxanthins. Data revealed that the ratio and concentration of betalain pigments are responsible for the color in the different cultivars, showing the highest betalains content in the fruit of purple colored Camuesa (O. robusta Wendl.) (8.1 mg/g dry fruit), which is comparable to that found in red beet Beta vulgaris L. ssp. Var. Pablo) (8.6 mg/g dry tissue). Yellow betalains were absent in Reyna (O. alba-carpa) prickly pear cultivar. A total of 24 known/unknown betalains were present in the prickly pear fruit samples studied, including 18 betaxanthins and 6 betacyanins. Our results indicate that prickly pear cultivars can be considered as a potential source of yellow and red natural colorants.  相似文献   

Large reductions in pesticides made possible by use of an insect‐trapping lamp: a case study in a winter wheat‐summer maize rotation system          下载免费PDF全文

Liyue Guo  Mahmud Abdimuratovich Muminov  Guanglei Wu  Xiaotian Liang  Caihong Li  Jie Meng  Lijun Li  Da Cheng  Yanjie Song  Xian Gu  Jianshe Zhao  Gaoming Jiang 《Pest management science》2018,74(7):1728-1735

  相似文献   

伊朗里海森林山坡上生长的欧洲鹅耳根系分布和抗张强度研究     

Ehsan Abdi Baris Majnounian Hassan Rahimi Mahmud Zobeiri 《林业研究》2009,20(2)

对生长在伊朗北部丘陵地带的8株欧洲鹅耳的根面积比率和根系拉伸强度进行了测定,评估了欧洲鹅耳根系生物力学特性。应用剖面挖掘法测得土层深度为0．1米的样品根面积比率。共用了123份根样品分析根系拉伸强度。结果表明,根面积比率随土层深度增加而减小,变化规律遵从幂函数;上坡面和下坡面根面积比率无统计差别。根系可达到的最大土层深度为0．75米,但是最大根面积比率存在于土层深度0．1米内。下坡面最小和最大根面积比率分别为0．004％和6．431％;而上坡面的根面积比率分别为0．004％和3．995％。上、下坡面根数无显著差异,而且90％以上的根系深入到50-60厘米的土层中。Spearman双变量相关性分析结果表明,根面积比率与根数无显著关系。平均根拉伸强度为31．51&#177;1．05MPa,且根系直径越粗根拉伸强度越小,遵从幂函数变化。图5表1参38。  相似文献   

Production of Biscuit from Chinese Sturgeon Fish Fillet Powder (Acipeneser sinensis): A Snack Food for Children     

Bereket Abraha  Abdu Mahmud  Habtamu Admassu  Habte-Michael Habte-Tsion  Fang Yang 《Journal Of Aquatic Food Product Technology》2013,22(10):1048-1062

ABSTRACT

Malnutrition in children is a current global burden. A common snack for children is biscuits prepared from cereals. However, these types of biscuits have low protein content. Therefore, producing healthier biscuits enriched with essential amino acids (EAAs) and other micronutrients is of great interest to researchers and manufacturers. In this study, biscuits produced from low gluten wheat flour fortified with sturgeon fillet powder (SFP) in various mixing ratios (100:0, 95:5, 93:7, and 90:10, respectively) were investigated. The results revealed that the nutritional and proximate composition of biscuits were significantly (P ≤ 0.05) improved: moisture (6.77 ± 0.06–7.65 ± 0.06), protein (13.23 ± 0.35–17.12 ± 0.02), fat (15.57 ± 0.18–15.85 ± 0.25), ash (0.84 ± 0.07–0.92 ± 0.06), spread ratio (14.0 ± 0.92–14.33 ± 0.21), and hardness (2,057.90 ± 28.33–3,089.02 ± 51.53). Total amino acids were 6.91, 9.34, 10.32, and 10.58; and EAAs were 2.43, 3.97, 4.48, and 4.22 g/100 g for 0%, 5%, 7%, and 10% SFP, respectively. Leucine was the major amino acid with 5% and 10% SFP, while methionine was the major amino acid with 7% SFP. Fungal counts were not observed, and quality indices were below the maximum acceptable limits in the products. Biscuits supplemented with 7% SFP showed the highest sensory evaluation score. Overall, the inclusion of 7% SFP could produce protein enriched cereal-based fortified biscuits with acceptable sensory and quality attributes and ultimately could insure effective fish utilization and solve malnutrition problems.  相似文献   

Production analysis of broiler farming in central Punjab,Pakistan     

Rahman  Naeem Ur  Mehmood  Shahid  Ahmad  Sohail  Javid  Arshad  Mahmud  Athar  Hussain  Jibran  Shaheen  Muhammad Shabir  Usman  Muhammad  Mohayud Din Hashmi  Syed Ghulam 《Tropical animal health and production》2020,52(3):1125-1131

Tropical Animal Health and Production - This study examined the analysis of personal and production performance of broiler farming in 10 cities of central Punjab (Lahore, Sheikhupura, Kasur, Okara,...  相似文献