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由夜公和野败的两个异质同核不育系分别与两个恢复系杂交,配制8个组合进行随机区组试验,在相同核背景下比较不同雄性不育细胞质对杂交水稻的影响。结果表明,夜公雄性不育细胞质对杂交水稻产量和主要农艺性状的影响优于野败,是一个可以开发利用的雄性不育细胞质。 相似文献
956.
Qiang Zeng Lihua Deng Wenbin Hu Xingjian He Qiucheng Meng Jianghui Yu Jinjiang Li Lushui Weng Guoying Xiao 《水稻科学》2020,27(3):215-226
Weeds and insect pests are two important biotic stresses resulting in yield loss in rice, and wide compatibility is the essential characteristic of breeding inter-subspecific hybrid rice. This study focused on glyphosate resistance, lepidopteran resistance and wide compatibility as well as identification of molecular and some agronomic characteristics of transgenic male sterile line E1 C4008 S. The results indicated that glyphosate resistance gene Epsps# and lepidopteran resistance gene Cry1 ca~# were transferred into japonica wide compatibility male sterile line 4008 S by Agrobacterium-mediated method, and four independent transformation events named E1 C4008 S-1, E1 C4008 S-2, E1 C4008 S-3 and E1 C4008 S-4 were obtained, in which E1 C4008 S-3 and E1 C4008 S-4 were of single copy insertion. The EPSPS protein contents of E1 C4008 S-3 and E1 C4008 S-4 in different organs were significantly different both in descending order of leaf stem root, and ranged from 300.58 to 1410.69 μg/g at the tillering stage. The glyphosate tolerable concentration(dosage) of E1 C4008 S-3 and E1 C4008 S-4 reached at least 16 g/L(54.42 kg/hm2), and the seeds of E1 C4008 S-4 can germinate normally on the medium containing 1 g/L glyphosate. The CRY1 C protein contents of E1 C4008 S-3 and E1 C4008 S-4 in different organs were significantly different both in descending order of leaf stem root, and ranged from 0.62 to 2.43 μg/g at the tillering stage. The larvae mortalities of rice leaf rollers fed on leaves of E1 C4008 S-3 and E1 C4008 S-4 for 5 d were 95.35% and 97.77%, respectively, while the average mortalities of silkworms fed with protein extracts from leaves of E1 C4008 S-3 and E1 C4008 S-4 reached 94.55% and 83.64%, respectively. The results suggested that wide compatibility and evaluated agronomic traits of E1 C4008 S-4 were not significantly changed by insertion of the exogenous genes. Overall, a novel male sterile germplasm with glyphosate resistance, lepidopteran resistance and wide compatibility was verified to be developed in rice. 相似文献
957.
Cultivar and seasonal effects on the contribution of pre-anthesis assimilates to safflower yield 总被引:2,自引:0,他引:2
Spyridon D. Koutroubas Despo K. Papakosta Alexandros Doitsinis 《Field Crops Research》2004,90(2-3):263-274
In crops grown under Mediterranean environments, translocation of pre-anthesis assimilates to the seed is of great importance for seed growth, because hot and dry conditions during the seed filling period diminish photosynthesis and crop nitrogen uptake. This field study was conducted to assess the genetic and seasonal variation in the amount of pre-anthesis dry matter and nitrogen accumulated and translocated to seed by safflower (Carthamus tinctorius L.) plants, and the possible N losses occurring between anthesis and maturity. Ten genotypes, 4 hybrids and 6 open pollinated cultivars, were grown for 2 growing seasons without irrigation, on a silty clay (Typic Xerorthent) soil. The proportion of dry matter and N content at anthesis that was translocated to seed differed among genotypes and ranged from 14.9 to 39.6 and from 24.8–59.3%, respectively. Genotypic differences in dry matter and N translocation were mainly associated with dry matter and N accumulated during the vegetative growth of the plants. Greater amounts of dry matter and N content at anthesis resulted in a greater dry matter and N translocation to seed during the filling period. When the N contents of aboveground plant parts at anthesis and maturity were compared, both gains and losses were observed, and were mainly related to the sink size. No N losses were detected when yield was high. When yield was low, N losses depended on N content at anthesis; high N content resulted in N losses, otherwise no N losses were observed. The contribution of pre-anthesis accumulated reserves to seed weight ranged from 64.7 to 92.2%, indicating the importance of pre-anthesis storage of assimilates for attaining high safflower yield. 相似文献
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959.
用人工冷水池鉴定水稻光温敏核不育系雄性不育起点温度的研究 总被引:7,自引:0,他引:7
用人工冷水池与人工气候箱分别对8个水稻光温敏核不育系在它们育志换温敏感期进行5d日均温23.5℃(22-25℃)的冷水与6d日均温23.5℃(19.5-26.0℃)的冷气处理。结果表明:株S-1、陆18S、96-5-2S、139S及康201S在两种低温处理条件下均表现不育,自交结实率与花粉可染率均为0;培矮64S在人工冷气处理条件下也表现不育,自交结实率与花粉可染率为0,但在人工冷水处理条件下表现轻度可育,自交结实率为0.05%,花粉可染率为5.0%;810S与179S在两种低温处理条件下均表现可育,自交结实率为3.7%-18.5%,花粉可染率为4.3%-41.0%,但人工冷水处理条件下的自交结实率与花粉可染率明显高于人工冷气处理条件下的自交结实率与花粉可染率。说明用人工冷水池鉴定水稻光温敏核不育系雄性不育的起点温度是可行的,而且鉴定的灵敏度比人工气候箱更高。根据人工冷水池与人工气候箱鉴定的结果可知:株S-1、陆18S、96-5-2S、139S及康201S的雄性不育起点温度小于23.5℃,培矮64S的雄性不育起点温度在23.5℃左右,而810S与179S的雄性不育起点温度大于23.5℃。 相似文献
960.
本研究旨在提高优质两系光温敏型核不育系‘荃211S’的白叶枯病抗性。以‘荃211S’为受体亲本,以含有抗白叶枯病Xa23基因的CBB23为供体亲本,通过分子标记辅助选择技术与常规育种技术相结合,筛选抗白叶病的不育株系。筛选出4个改良不育株系QK211S-1~QK211S-4。改良‘荃211S’株系的农艺性状、育性转换温度、异交结实率与‘荃211S’相近,但在白叶枯病抗性上明显增强,表现出高抗或抗,抗性级别0~2。改良‘荃211S’株系所配组合与‘荃211S’所配组合在株高、每穗总粒数、结实率、千粒重的差异不显著,但白叶枯病抗性显著增强,抗性级别为1,高抗。改良的4个‘荃211S’株系为选育抗病水稻品种奠定了基础,可以直接在生产中应用。 相似文献