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61.
以黑龙江垦区2006年~2008年区域生产试验的64个水稻品种(系)为材料,分析了2个熟期3a试验的平均产量与产量构成因素的关系。结果表明:在高产育种中,不同熟期应有不同的选择标准。中熟组应选分蘖中等、大穗的品种,早熟组应选择结实率高、穗数型品种。2个熟期高产育种的共同点是都应选择结实率较高的水稻品种。 相似文献
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63.
Inducible responses in plants against pathogen attack play a major role in resistance to disease. The defense responses are
mostly associated with the expression of various kinds of inducible genes. We employed differential hybridization to isolate
elicitor-inducible genes (EIGs) of tobacco (Nicotiana tabacum cv. Samsun NN) using the tobacco-fungal elicitor system. A cDNA library was constructed from tobacco leaves treated for 12
hr with hyphal wall components (HWC) prepared from Phytophthora infestans, and six EIGs were identified. Expression of all EIGs was induced after inoculation with the soybean pathogen Pseudomonas syringae pv. glycinea (nonpathogenic on tobacco) or treatment with salicylic acid, and a variety of expression patterns of EIG mRNAs was observed.
Sequence analysis of EIG cDNAs revealed similarities to genes for SAR8.2 (EIG-B39 and EIG-D14), glycine-rich protein (EIG-G7), extensin (EIG-I30), acyltransferase (EIG-I24) and unknown protein (EIG-J7). Possible roles of EIG products in disease resistance are discussed.
Received 30 August 2000/ Accepted in revised form 30 November 2000 相似文献
64.
The activity levels of succinate dehydrogenase (SDH) and glucose‐6‐phosphate dehydrogenase (G6PD) were assessed in various tissues of Cyprinus carpio var communis which had been exposed to lethal concentrations of group‐II pyrethroids (deltamethrin, cypermethrin, fenvalerate and fluvalinate) for a period of 72 h. The results indicated a steady decrease in SDH activity with a concomitant increase in G6PD activity. The decreased SDH activity indicated inhibition of SDH at mitochondrial level and the increased G6PD activity an enhancement of an alternative pathway of carbohydrate metabolism, viz the hexose monophosphate shunt (HMP) or pentose phosphate pathway as a biochemical adaptation to overcome the toxic stress. © 2001 Society of Chemical Industry 相似文献
65.
A. F. Ibrahim A. N. Sharaan A. W. El Wakil 《Journal of Agronomy and Crop Science》1991,167(3):170-175
Two promising selected land races of safflower ( Carthamns tinctorious L.) designated as line 11 and line 13, together with the local variety Giza 1 , were examined under three levels of moisture depletions, i.e. 40, 60 and 80 % ASMD at Fayoum, Middle Egypt during 1986/87 and 1987/88 seasons. In both growing seasons, the second irrigation treatment i.e. 60 % ASMD gave the highest means for growth characters as well as seed yield and most of its components. Seed oil content per cent exhibited an increased as soil moisture depletion increased with no significant difference between entries. Safflower entries showed clear differences in some yield components which compensate each other and resulted in no significant difference in seed yield per hectar.
Consumptive use of water by safflower plants increased as the available soil moisture around the root zone increased. No significant differences were found in water consumed by safflower entries used in all experiments.
In the two experimental seasons, the best water use efficiency (WUE) for seed production was obtained also from the second treatment (60 % ASMD). The line 11 gave the best WUE. 相似文献
Consumptive use of water by safflower plants increased as the available soil moisture around the root zone increased. No significant differences were found in water consumed by safflower entries used in all experiments.
In the two experimental seasons, the best water use efficiency (WUE) for seed production was obtained also from the second treatment (60 % ASMD). The line 11 gave the best WUE. 相似文献
66.
“协调型”小麦新品种的产量潜力及其构成的研究 总被引:2,自引:0,他引:2
研究证明,小麦分蘖成穗与生态条件的关系存在着品种间的变异。按这个思路,成功地培育出了"协调型"系列小麦品种,它们不同于四川盆地其他品种:它们能在保持较大穗重的情况下有较高的成穗数。研究表明:与对照品种川麦28相比,"协调型"小麦新品种的产量潜力有所提高,产量构成也发生了较大的变化,单位面积的成穗数明显高于对照。协调型小麦新品种成穗数较高的原因,除了较强的分蘖能力外,主要在于它们有更高的分蘖成穗能力。协调型小麦新品种增产的主要原因是因为在较大穗重的情况下较高的成穗数使生物产量显著增加。"协调型"小麦新品种的选育为改变四川盆地小麦品种类型现状,提供了新的模式。 相似文献
67.
68.
69.
穴播条件下株行距对紫花苜蓿种子产量和质量的影响 总被引:6,自引:1,他引:6
在甘肃省酒泉市研究了穴播条件下不同株、行距处理对紫花苜蓿种子生产性能的影响,结果表明:在产种第一年(2004年)行距和株距对种子产量和产量构成因素均产生了显著的影响(P〈0.05),随着行距从60cm递增至100cm,种子产量也随之从1240kg/hm^2下降到982kg/hm^2,而各株距处理的种子产量则从15cm的1426kg/hm^2依次递减至60cm的807kg/hm^2;行距60cm和株距15cm组合的产量最高,为1833kg/hm^2,100cm行距和株距60cm组合的产量最低,为753kg/hm^2。株行距的增加显著降低了枝条密度,但结荚花序数/枝条和荚果数/结荚花序却显著提高。品种间种子产量的差异不显著。品种间的结荚花序数/枝条、种子重量、正常种苗率、发芽势和硬实率存在显著的差异(P〈0.05)。 相似文献
70.
四种鲜牛肝菌成分分析 总被引:1,自引:0,他引:1
采用原子吸收分光光度法、比色法等方法对美味牛肝菌、华美牛肝菌、美柄牛肝菌和绒柄牛肝菌4种鲜牛肝菌的粗蛋白、粗脂肪、矿质元素、有害元素的含量进行测定.结果表明,4种鲜牛肝菌中,粗蛋白、粗脂肪、总糖和粗纤维的含量范围分别是4.38%~5.42%、2.47%~3.07%、1.26%~3.85%、1.23%~1.56%;矿质元素铁、锌、钙的含量范围分别是19.62~37.96mg/kg、6.53~9.67mg/kg、146.23~298.02mg/kg;总砷含量未检出,有害元素总汞、铅、镉的含量范围分别是0.06~0.73mg/kg、0.4~0.62mg/kg、0.075~0.105mg/kg.结论:这4种野生鲜牛肝菌含有丰富的营养成分,但华美牛肝菌、美柄牛肝菌中总汞含量较高,值得关注. 相似文献