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1.
光照不仅会影响植物自身的生长,也可能会对其子代的生长具有潜在作用。以箭筈豌豆品种兰箭1号和兰箭3号为材料,分析遮荫和自然光照下箭筈豌豆及其子代的生长特性。结果表明:光照对箭筈豌豆生长和繁殖特性的影响因基因型而异。与光照条件相比,遮荫显著降低兰箭1号生物量及茎叶比,但对繁殖分配的比例影响不显著。与此相反,遮荫对兰箭3号的生长与繁殖无显著影响;母本光照环境对箭筈豌豆子代生长特性具有一定程度的影响,且这种影响因子代植株生长的光照环境而异。当子代在遮荫环境下,母本环境显著影响兰箭1号分枝数、地上生物量、总生物量、地上/地下生物量以及兰箭3号的分枝数。但当子代在光照环境下生长时,除兰箭3号分枝数外,其他生长特性均不受母本环境影响。  相似文献   
2.
辛夏青  魏小红  韩厅  岳凯  赵颖 《草业学报》2018,27(10):105-112
以紫花苜蓿为材料,用一氧化氮供体硝普钠(SNP)及一氧化氮清除剂c-PTIO对苜蓿种子进行浸种处理,采用分光光度法和同工酶电泳技术来研究外源NO及反向调控对PEG胁迫下紫花苜蓿抗氧化酶活性及其同工酶的影响,并探讨NO调控苜蓿种子耐旱性的生理机制。结果表明:PEG胁迫下外施0.1 mmol·L-1 SNP,第6天时较PEG处理POD活性降低了32.72%;第4天时SOD、CAT活性较PEG处理升高了10.48%、23.60%,有效缓解了PEG对紫花苜蓿萌发中种子的氧化损伤,提高其抗氧化能力。PEG胁迫下添加 c-PTIO抑制了苜蓿萌发期的抗氧化系统活性。从同工酶的谱带数量和强弱来看,POD同工酶各区带活力均随PEG胁迫时间的延长而增加,在第2天酶带只有1条,而第4天酶带呈现9条;SOD和CAT同工酶表达量变化不显著,但酶带强弱有一定变化,S3酶带随处理时间的延长表达量逐渐减弱;CAT同工酶谱带则一直保持2条带,无明显强弱变化。因此,外源NO在PEG胁迫下紫花苜蓿萌发中抗氧化酶快速响应并在维护氧自由基代谢平衡中起重要保护作用。  相似文献   
3.
1997~1999年对收集引进的22个枣品种进行生长和结果情况调查及物候期定点预测,以大荔圆枣为对照,从丰产性、品质、抗性(抗裂果)、单果重、结果整齐度5个方面进行综合评比,筛选出适宜我省发展的不同用途的枣树优良品种12个,为黄土高原红枣产业化发展提供了品种依据。  相似文献   
4.
研究了箭舌豌豆不同器官对种子产量的贡献,结果表明:箭舌豌豆种子利用花后光合产物较多,不同器管对箭舌豌豆种子产量的贡献是复叶〉茎〉托叶,叶片对种子产量的贡献与其所在位置有关,花后叶因离荚果较近,其光合产物易于向荚果运输。  相似文献   
5.
模糊评分法在高羊茅品种综合评价中的应用   总被引:3,自引:1,他引:2  
1999--2001年对引进和培育的高羊茅新品种(系)在喀斯特生态区进行品种比较试验。观测记裁各参试品种的性状表现,对春、夏、秋、冬4个季节的观测结果,用模糊评分法Ⅲ进行分析比较,并按综合评价值的大小排序a结果高羊茅“98--1”的综合评价值最大,排第一名,依次是猎狗5号、矮星2号、凌志(对照),其余参试品种排名次后。认为用模糊评分法对高羊茅品种进行分析评价是可行的。  相似文献   
6.
Time course of grain filling pattern in two rice (Oryza sativa L.) cultivars, grown under normal and low light intensities, was studied. The number of spikelets, partially filled grains and high density grains were monitored at a 5 day interval during grain filling period from uniform panicles tagged at anthesis. The low light tolerant cultivar Swarnaprabha had more high density grains and less partially filled grains throughout the grain filling period and at harvest compared to cultivar Ratna under both normal and low light intensities. Further, the opening of spikelets in two flushes in Swarnaprabha seemed to result in a more efficient resource allocation and hence better yield as compared to Ratna, in which the opening of spikelets was in a single flush on day 10.  相似文献   
7.
干椒1号是由母本二金条-12-6-4和父本羊角-2-3配制的一代杂交种。该品种早熟,高抗病毒病、疫病,耐寒、耐热、耐湿、耐瘠。果实细长羊角形,青椒绿色,老熟果鲜红色,果皮薄、籽少、味辣,易脱水,晒干率高,宜作晒干椒或鲜食。一般667m^2产鲜红椒2500kg,或干椒800kg。全国各地均宜种植,特别适宜嗜辣、习惯晒干椒的地区大面积推广。  相似文献   
8.
Inheritance process for β-glucan content in oat caryopsis
Due to the fact that there are only few studies concerning β-glucans in oat caryopsis with regard to plant-breeding aspects, three oat crosses were performed (cross 19 = low × high, cross 86 = low × low, cross 98 = high × high). In all of the three oat crosses, lower β-glucan content (% DM) was recorded in F, than in F, indicating that the β-glucan content (% DM) at a higher heterozygoty grade is lower than at a reduced heterozygoty grade. This points to a dominant inheritance of lower β-glucan content (% DM). A tendency towards the female β-glucan content (% DM) could not be proven. Thus, it can be started from a nuclear genetic inheritance of the β-glucan content (% DM). In most cases, the experiments showed a normal distribution of β-glucan content (% DM), indicating for several genes a quantitative inheritance of β-glucan content (% DM). By means of the regression of the F3-lines to the F2-plants, the narrow-sense heritability could be calculated for the cross 86 (h2= 0.51***) and the cross 98 (h2= 0.48***). The heritability for the cross 19 was not significant.  相似文献   
9.
A spontaneously occurring rice (Oryza sativa L. ) mutant, characterized by homeotic conversion in glumes and stamens, was found in the progeny of a cross. The mutant showed long glumes and glumaceous lodicules and morphological transformation of stamens into pistils. Mutant florets consisted of 1 to 3 completely developed pistils, some pistilloid stamens with filaments, but tipped by bulged tissue and 0 to 3 stigmas. It seens that the mutant phenotype of the homeotic conversions in glumes and stamens is similar to that of the B loss-of-function mutants in Arabidopsis and Antirrhinum. The mutant is controlled by a single recessive gene as a segregation ratio of 3:1 (wild type to mutant plants) was observed in the F2 generation.  相似文献   
10.
Three oat (Avena saliva L.) populations (i.e., lines of descent), high grain yield (HG), high protein content (HP), and high protein yield per se (HGP), each developed by three cycles of S, recurrent selection, were evaluated for the effect of selection for groat-protein yield upon other agronomic traits. Selections making up the HG line of descent had high protein yield primarily due to high grain yield, and those selected for HP had high protein yield due to both high protein content and high grain yield. Selection in HGP was on the basis of protein yield per se. Selection caused increases in bundle weight, harvest index, vegetative growth rate, and seed number in all lines of descent. Heading date, plant height, and seed weight were unaffected, whereas groat percentage and test weight were decreased in HP and HGP. Heritabilities were high for heading date, plant height, test weight, and seed weight, moderate for harvest index and bundle weight, and low for groat percentage. Genetic variability generally declined from CO to C3 for all traits. Groat-protein yield and amount of protein per groat increased in all lines of descent. In HG, the increase in groat weight was due primarily to increases in the nonprotein fraction, with groat-protein content actually decreasing. In HGP, groat weight increased due to increases in protein and nonprotein fractions, and groat protein content remained constant. In HP, groat weight and amount of nonprotein per groat decreased, thus increasing groat-protein content. Three cycles of recurrent selection resulted in oat lines with groat-protein yields significantly higher than the highest lines from CO. Utilization of index selection may be desirable to obtain populations of greater breeding value.  相似文献   
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