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91.
海丰长茄1 号是以双单倍体(DH)株系02-QP-19 为母本,优良自交系A-40 为父本配制而成的长茄一代杂种。平
均始花节位为第9 节,植株生长势强,叶片绿色,叶脉、叶柄和主茎的颜色为紫色,植株半开张类型。果实平均纵径31.5
cm,横径4.5 cm,果皮紫黑色,有光泽,果实顶部尖,平均单果质量220 g,VC 和VP 的含量分别为23.2 mg·kg-1 和0.035%。
一般每667 m2 产量5 000 kg 左右。适宜北京、吉林和黑龙江等地区露地种植。  相似文献   
92.
随着网络教育的发展,接受网络教育和考试认证的人越来越多,在线考试正在得以迅速发展.本文简要介绍在线系统工作原理和系统配置.  相似文献   
93.
研究9个不同施肥处理对枳及柠檬容器苗生长的影响。结果表明:不同施肥处理对枳容器苗的苗高、地径、分枝高度及嫁接后柠檬苗的发芽率、株高、茎粗、分枝数及生物量都存在显著差异;不同施肥处理对枳及柠檬容器苗综合表现最好的为T4(撒施柠檬专用肥1.6 g)处理,其次是T2(撒施尿素0.6 g)、T3(撒施柠檬专用肥0.8 g)处理,表现最差的是T8(浇施5%柠檬专用肥)和T7(浇施3%柠檬专用肥)处理。在一定施肥浓度范围内,施肥对嫁接后柠檬容器苗的生物量积累有明显促进作用。柠檬容器苗培育时建议采用在基质中撒施柠檬专用肥1.6 g。  相似文献   
94.
Sustainable and profitable commercial aquaculture production of marine fish species is dependent on the development of sustainable protein sources as substitutes for expensive animal meals such as fishmeal (FM). Previous Florida pompano Trachinotus carolinus studies have indicated that poultry by‐product meal (PBM) and meat and bone meal can be used to produce a FM‐free diet if suitable levels of nutrients (such as taurine) are included in the diets. In this study, we attempted to develop an all‐plant protein diet by removing the animal proteins in practical diets for pompano by substituting back select ingredients. A series of eight FM‐free diets were formulated, four systematically replaced soybean meal (SBM) with soy protein concentrate (SPC) and four replaced PBM with SPC. Based on the results, there is no clear disadvantage to the use of SPC as a replacement for SBM. However, the complete removal of PBM resulted in reduced performance. Two additional growth trials were conducted to supplement additional amino acids including glycine, valine and histidine, a proprietary chemical attractant mix, fish protein concentrate and squid hydrolysate to improve the growth of pompano when fed all‐plant protein diets. The only improvement in performance occurred with the squid hydrolysate. These results demonstrate that using soybean meal, soy protein concentrate and corn gluten meal as the primary protein sources, a plant‐based feed formulation can be developed, but the removal of all animal proteins is not yet feasible.  相似文献   
95.
The application of probiotics in food is now widespread and is widely accepted by consumers. Lactic Acid Bacteria (LAB) were isolated from traditional salted fish and then characterized by its ability to inhibit Vibrio parahaemolyticus growth using minimal inhibitory concentration tests. Five out of these strains were identified as Lactobacillus delbrueckii, Lactobacillus casei and three Lactobacillus gasseri by PCR using 16S and 23S rRNA genes. Antibiofilm activity of Lactobacillus spp. extracts were also tested in 96 polystyrene plates. A potential antibiofilm effect was demonstrated as most LAB. Although most LAB extract were able to eradicate pre‐formed biofilm, results demonstrated that five Lactobacillus spp. exhibited a stronger inhibitory effect against V. parahaemolyticus in infected oysters. Vibrio parahaemolyticus viable cells number declined from 106 UFC to 104 UFC after 3 days of incubation with Lactobacillus spp. Probiotic applications, in biological control of seafood associated pathogens can be an alternative solution, providing consumer with a product of good quality owing to the use of non‐toxic compounds. Based on our results, LAB could be used as a bioprotective culture in oyster's depuration to prevent V. parahaemolyticus growth.  相似文献   
96.
To investigate the nutritional value of the marine micro‐alga Isochrysis galbana Tahitian Isochrysis strain (T.iso) as an alternative feed for aquaculture during culture age, its biochemical composition was studied under autotrophic and controlled culture conditions at different growth stages: exponential phase, early and late stationary phases and decay phase. Analysis showed that C14:0, C16:0, C16:1, C18:4 (n‐3) and C22:6 (n‐3) were the most abundant fatty acids in this alga at different growth stages. The highest values of monounsaturated fatty acids were recorded at the late stationary and the decay phases. However, the highest levels of polyunsaturated fatty acids were observed at the early stationary phase. At all growth stages, I. galbana (T.iso) contained arabinose, xylose, mannose, galactose and glucose. Glucose represented the main sugar, and its content per dry alga biomass weight increased with increasing age of the culture and reached about fourfold in the decay phase. The maximum protein content was also observed during this last phase.  相似文献   
97.
With continuous outbreaks of stripe rust (Puccinia striiformis f. sp. tritici) epidemics and rapid breakdown of deployed resistance in bread wheat (Triticum aestivum L.) cultivars in North West Plains Zone (NWPZ) in India warrant knowledge and deployment of new and durable sources of resistance to stripe rust. Bread wheat cultivar PBW 343, until recently the most widely cultivated wheat variety in India, is now highly susceptible to stripe rust (score 9 on a 1–9 scale), whereas PBW 621 (score 5.05–5.65) and HD 2967 (score 5.40–6.20) show low levels of resistance. We conducted an experiment, spanning three crop seasons (2013–2014 to 2015–2016), in which parental lines, F1 and F2 populations, F3 and F4 families from two bread wheat crosses, PBW 621/PBW 343 and HD 2967/PBW 343 were generated and evaluated for stripe rust resistance against a virulent pathotype. While the F1 revealed partial dominance, the segregation pattern for stripe rust resistance in F2 and F3 showed transgressive segregation for resistance in both crosses. Chi-square analysis indicated that resistant segregants possessed two genes, one contributed by PBW 621 or HD 2967 (depending on the cross) and the other, unexpectedly but obviously, came from the most susceptible cultivar, PBW 343. Possible genetic mechanisms for this residual resistance and implications for breeding programs are discussed.  相似文献   
98.
To provide food and nutrition security for a growing world population, continued improvements in the yield and nutritional quality of agricultural crops will be required. Wheat is an important source of calories, protein and micronutrients and is thus a priority to breed for improvements in these traits. The GRAIN PROTEIN CONTENT-B1 (GPC-B1) gene is a positive regulator of nutrient translocation which increases protein, iron and zinc concentration in the wheat grain. In the ten years since it was cloned, the impacts of GPC-B1 allelic variation on quality and yield traits have been extensively analyzed in diverse genetic backgrounds in field studies spanning forty environments and seven countries. In this review, we compile data from twenty-five studies to summarize the impact of GPC-B1 allelic variation on fifty different traits. Taken together, the results demonstrate that the functional copy of the GPC-B1 gene is associated with consistent positive effects on grain protein, Fe and Zn content with only marginally negative impacts on yield. We conclude that the GPC-B1 gene has the potential to increase nutritional and end use quality in a wide range of modern cultivars and environments and discuss the possibilities for its application in wheat breeding.  相似文献   
99.
Shrimp cultivation has been faced with huge losses in productivity caused by infectious shrimp pathogenic vibrios, especially Vibrio parahaemolyticus that causes acute hepatopancreatic necrosis disease (AHPND). Hence, purple nonsulphur bacteria (PNSB) were isolated from shrimp ponds for investigating their abilities to control shrimp pathogenic Vibrio spp. and their use as probiotics for sustainable shrimp cultivation. Based on their probiotic properties, strains S3W10 and SS15 were selected because of their strong abilities to produce amylase, gelatinase and vitamin B12. However, only three PNSB strains (SS15, TKW17 and STW181) strongly inhibited V. harveyi_KSAAHRC and V. vulnificus_KSAAHRC including V. parahaemolyticusAHPND strains by secreting antivibrio compounds. Four selected PNSB also grew in the presence of pancreatic enzymes, and they were identified as Rhodobacter sphaeroides for strains S3W10, SS15 and TKW17 and Afifella marina for strain STW181. The effects of a mixed culture were also investigated as follows: T1 (S3W10 + SS15), T2 (S3W10 + TKW17) and T3 (S3W10 + STW181) on postlarval white shrimp (Litopenaeus vannamei) for 60 days by comparison with a control. All three probiotic PNSB sets significantly improved the digestive enzyme activities and shrimp growth with their proliferation in shrimp gastrointestinal tract although the shrimp survival was not significantly different. They also significantly reduced the cumulative mortality of shrimp exposed to a virulent AHPND strain (V. parahaemolyticusSR2). This is the first to conclude that selected probiotic PNSB strains have great potential to be used for shrimp cultivation to control vibrios including AHPND strains.  相似文献   
100.
【目的】探索太白山锐齿槲栎林林下草本植物组成和多样性与环境因子的关系,为该区域森林保护、经营管理提供理论指导。【方法】基于太白山锐齿槲栎林林下草本植物野外调查及室内试验数据,采用CCA和偏CCA排序法分析环境因子对太白山锐齿槲栎林林下草本植物组成的影响,采用相关分析和多元逐步回归分析探索环境因子对其草本植物多样性的影响。【结果】环境因子能显著解释太白山锐齿槲栎林林下草本植物组成变异,海拔、坡向、坡度、pH、枯落物厚度和有机质、碱解N、有效P、有效K含量及郁闭度、灌木盖度11个环境因子共解释了物种组成变异的39.05%。其中,郁闭度、土壤有效P含量、pH值和海拔是影响林下草本植物组成的主要环境因子。海拔、郁闭度、有效P和有效K含量能够显著影响太白山锐齿槲栎林林下草本植物的多样性,海拔较高、郁闭度较大、土壤有效P和有效K含量较高的生境具有较好的草本植物多样性。【结论】在太白山锐齿槲栎林经营管理中,可通过适量施用P肥和K肥来促进林下草本植物发育,提高物种多样性。  相似文献   
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