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211.
212.
Summary Inheritance of raw cucumber fruit texture (Magness-Taylor Fruit Pressure Tester firmness) was investigated over a 4-year period from 1971–1974. Results from 2 separate but related experiments suggested that firmness was quantitatively inherited with sufficient additive effects to permit gain from selection. In a selection study within 4 F2 populations derived from crosses between firm (Chipper and Gy3) and soft (Mincu and Green F) fruit type cultivars, variation among and within F3 and F4 families was significant but overall family means were not significantly higher than the high parent in any of the 4 crosses. Narrow sense heritability estimates for fruit texture were 0.80 in the Mincu × Chipper population and 0.77 in the Green F × Chipper, Mincu × Gy3, and Gy3 × Green F crosses. In a separate experiment, generation means analysis was used to assess the mode of gene action in 2 crosses: Green F × Chipper, and Gy3 × Green F. Additive genetic effects accounted for 98.8% and 99.3% of the total genetic variation within each cross, respectively.Scientific Journal Series Paper No. 9794. 相似文献
213.
Summary
Cucumis sativus var. hardwickii (Royle) Alef., the wild progenitor of cultivated C. sativus is reported for the first time from peninsular India. The South Indian specimens showed n=7 bivalents in PMCs. The discontinous occurrence of the wild taxon in the Himalayan regions and peninsular hills and the existence of cultivars of C. sativus adapted to the tropical and temperate climates suggest polytopic domestication of the cultivated forms. The possibility of utilizing this wild germplasm for crop improvement is indicated. 相似文献
214.
Summary Experiments conducted in the greenhouse and in the field indicated that plants produced from seedlings of Cucumis sativus L. which displayed their cotyledons in an upward position grew faster than plants which displayed their cotyledons in a downward position. Cotyledon angle was not a function of seed size nor seedling weight at 10 days after planting. An increase in plant height, node number, and fresh weight at later growth stages was associated with an upward cotyledon angle and persisted until time of harvest. Anthesis tended to occur later in plants having a downward cotyledon angle. The number of pistillate flowers was greater in plants with an upward cotyledon angle compared to those with a downward cotyledon angle. Differences in yield (fruit number) were not associated with cotyledon angle.Paper No. 5432 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, NC. The use of trade names in this publication does not imply endorsement by the North Carolina Agricultural Experiment Station of products named, nor criticism of similar ones not mentioned. 相似文献
215.
为确定合理的包膜尿素用量以指导黄瓜育苗施肥,采用生产中常用的草炭:蛭石(2:1)为育苗基质,研究了包膜尿素不同用量对黄瓜幼苗生长、养分吸收及氮平衡的影响。结果表明:包膜尿素用量在125~375 mg N/株的情况下,可协调黄瓜幼苗地上部和地下部的生长,促进幼苗对磷、钾的吸收;移栽时,基质中的氮素残留总量90.5~250.3 mg N/株,其中,残留的包膜氮素占75.4%~82.3%,可实现带肥移栽;育苗期间可产生31.9~121.5 mg N/钵的氮素表观损失。 相似文献
216.
黄瓜茉莉花茶保健饮料的研制 总被引:2,自引:0,他引:2
以黄瓜、茉莉花茶为主要原料,配以适量的白砂糖和柠檬酸,研制黄瓜茉莉花茶保健饮料。结果表明,黄瓜茉莉花茶保健饮料的最佳配方为:黄瓜汁20%,茉莉花茶汁40%,白砂糖10%,柠檬酸0.15%;稳定剂选用0.2%的海藻酸钠、耐酸性CMC-Na、黄原胶的混合液(1∶1∶1)对饮料的稳定效果最好。按此配方制作的饮料呈淡绿色,口感清爽,营养丰富,具有黄瓜和茉莉花茶混合的特殊滋味与香气。 相似文献
217.
Summary The effect of self-pollination of cucumber (Cucumis sativus L.) for 6 generations in lines developed from the North Carolina Medium Base Pickle population was determined by regression of trait expression for each generation on Wright's coefficient of inbreeding. Two yield traits (total and marketable), earliness and 3 fruit quality traits (shape, color and seedcell size) were evaluated in 2 environments (spring and summer, 1983). The regression did not result in significant negative slopes, indicating that inbreeding depression was not important in the population for the traits studied. Midparent heterosis was found for most traits in many hybrids obtained from crossing S6 lines with the gynoecious inbred line, Gy 14A. 相似文献
218.
Summary The production, vigour, and fertility of F1 hybrids between nine African species of the genus Cucumis L. were studied as a measure of the relationships between the species. Hybrid plants were obtained from 29 out of the 72 possible cross combinations. Two F1 hybrids died as seedlings, and 27 hybrids were raised to maturity. Pollen production and stainability varied greatly amongst these hybrids, as did fruit and seed set following self pollination and backcrossing with either parental species. The fruit shape of the hybrids was always intermediate between that of both parental species.Two species appeared to be closely related: C. prophetarum L. and C. anguria var. longipes
A. Meeuse. Most other species produced highly to moderately fertile F1 hybrids with at least one other species. C. metuliferus
Naud. produced only sterile hybrids with C. zeyheri
Sond. 2x. The results sustain the recent taxonomic classification of the genus (Jeffrey, 1980). 相似文献
219.
三种主要黄瓜病毒抗性基因的定位 总被引:6,自引:0,他引:6
以黄瓜(Cucumis sativus L.)欧洲八号×秋棚为亲本构建的重组自交系(RIL)群体为材料,以病情指数为指标,对群体和亲本进行了小西葫芦(Cucurbitapepo L.)黄化花叶病毒(Zucchini yellow mosaic virus,ZYMV)、番木瓜环斑病毒西瓜株系(Papaya ringspot virus watermelon strain,PRSV-W)和西瓜花叶病毒(Watermelon mosaic virus,WMV)的抗病性鉴定.结果表明3种病毒的病情指数在黄瓜RIL群体呈双峰分布,表明对ZYMV、PRSV-W和WMV的抗性是受主基因控制的性状.利用Joinmap软件进行连锁分析,发现ZYMV和PRSV-W与WMV连锁,3个抗病基因的排列顺序和遗传距离是WMV-6cM-ZYMV-7cM-PRSV-W.根据AFLP、SSR和RAPD标记结果构建了一个黄瓜遗传图谱,3个抗病毒病基因被定位于第二连锁群. 相似文献
220.
秸秆和地膜双元覆盖对设施黄瓜根系生长和根际土壤养分的影响 总被引:2,自引:0,他引:2
[目的]研究秸秆和地膜双元覆盖条件对设施黄瓜结果期根系生长和根际土壤养分含量的影响,为北方寒旱区设施农业可持续生产提供理论依据和技术支持。[方法]以设施黄瓜为试材,采用日光温室试验和室内测定的分析方法。[结果]玉米秸秆加地膜的双元覆盖处理可明显增加根际土壤有机质、氮、磷、钾等养分含量,促进植株根系生长,其中0.72kg/m2秸秆量并覆膜处理效果和推广性最佳,与对照相比,在结果后期提高根际土壤有机质、全磷、全钾、碱解氮含量及根系数、根冠比、总根长、根表面积、根系活力分别达20.83%,22.83%,5.16%,5.53%,73.24%,32.76%,65.42%,45.94%和10.41%。[结论]秸秆和地膜复合的双元覆盖效果优于秸秆或地膜单一覆盖处理。 相似文献