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51.
高粱不同分类组杂种优势和配合力的研究   总被引:5,自引:0,他引:5  
以3份高粱不育系和24份恢复系组配的72个杂交种及其亲本为试材,研究了不同高粱分类组的杂种优势和配合力。结果表明,7种性状的总平均优势为121.5%。株高和穗长正优势占98.6%和97.1%,产量和产量组分在52.8%~81.9%之间,出苗至50%开花日数负优势占87.5%。不同分类组小区产量、穗粒重和穗粒数的杂种优势差异较大,除穗粒数外,顶尖族组和混合族组的平均超高亲优势水平和次数都高于都拉族组。顶尖族组的SC72614和SC5414,都拉族组的S21014和混合族组的SC37014和S11014E的产量及其多数产量组分具一般配合力正效应,并达到显著或极显著平准。在10个最高产杂交种中,父本是顶尖族的6个,属顶尖工艺群;父本是混合族组的4个,分属惹拉—惹拉、顶尖—考拉和浅黑—菲特瑞塔工艺群。因此,从顶尖族和混合族组里选择亲本更易获得强优势杂交种。  相似文献   
52.
Landrace cultivars represent potentially valuable source material for breeding dual-purpose (grain and stover) sorghums. To characterize the genetic variation and interrelationships for major agronomic traits among potential dual-purpose sorghum landraces, 74 accessions, primarily from Southern Africa, the Sudan, and India, were evaluated in five environments at Patancheru, India. These environments, at 17°N with 520-540 mm rainfall during the growing season, are representative of the major sorghum-growing areas in India and the Sudanian Zone of Western and Central Africa. Significant genetic variation and high heritabilities (P = 0.01, h2= 0.63-0.92) were observed for seedling vigour, grain and stover yields, growth rate and harvest index. Time to flower was correlated with stover yield (r = 0.48, P = 0.01) and an index (Iev) of total economic value (r = 0.44, P = 0.01) but not with grain yield (r = 0.22, P = 0.05). Grain and stover yields varied independently (r = 0.22, P = 0.05) and were similarly related to Iev, values (r = 0.79 and r = 0.77 (P = 0.01), respectively). The 13 landraces with the highest Iev values (adjusted for maturity) had above-average growth rates and harvest indices that ranged from 20 to 38%. Landraces from Botswana and India were more highly represented in the high Iev set than in the full set of accessions.  相似文献   
53.
研究了雄性不育系高粱11A与苏丹草3个杂交组合F1代的生育、产量、光合性能等主要农艺特性及细胞遗传学特性。结果表明,3个杂交组合F1代的生长势和平均株高均明显超过其各自父本苏丹草,继承了苏丹草分蘖能力强和高粱11A抗倒伏的优良特性,生育期126~130 d,穗型呈双亲中间型;F1代花粉可育率均高达93%以上,结实性好,自然结实率62.34%~68.75%,杂交组合间差异不明显;F1代PMCMⅠ的平均染色体构型均为2n=2x=20(10Ⅱ),配对行为较规则,但棒状二价体频率明显高于其3个父本苏丹草和母本高粱11A,原亲本间遗传组成存在一定差异。综合分析植株生长、产量性状、光合性能等指标,得出3个杂交组合F1代的育种潜力依次为:高粱11A×棕壳苏丹草F1≥高粱11A×黑壳苏丹草F1>高粱11A×白壳苏丹草F1。  相似文献   
54.
高粱—苏丹草杂交种的应用可行性研究及其选育   总被引:8,自引:0,他引:8  
孙半钧  王云 《草业学报》1999,8(3):39-39
利用生产上推广的6个粒用高粱杂交种和4个高粱杂交种为对照,与随机组配的15个高粱-苏丹草杂交种进行比较。结果表明,高粱-苏丹草杂交种做饲用生产能力上仅次于甜高粱杂交种,但在早熟优质等若干特性上优于甜高粱,有些组合还高于甜高粱杂交种的生产能力。该类型杂交种干物质及绿色体的日生产能力高于甜杂2号21.1%和41.2%,原因是杂最高。  相似文献   
55.
ABSTRACT

The sugar-accumulating potential of global and local sweet and grain sorghum varieties were tested under the local conditions. The basis for this study was the dependency of sugar accumulation on temperature and photoperiod. Thus, the efficacy of cultivars as a bioenergy source would need to be determined based on their performance under the local environmental conditions. A strong correlation of sucrose content with brix was observed, enabling large-scale screening of varieties for high sucrose content. The morphological characteristics inherent in sweet sorghum, such as tall stems, greater number of leaves and a longer vegetative period, were found to correlate with the total stem sugar content. Assessment of sugars along the stem revealed maximum sugar accumulation in the upper intermediate to upper internodes in most of the varieties tested. The maximum theoretical ethanol yield (MTEY), a function of brix and juice yield, was determined as a better indicator of testing the performance of a variety as a potential source of bioethanol, mainly due to a negative correlation of stem juiciness and sucrose content in the varieties tested. Further, the relative expression of vacuolar invertase genes, SbINV1 and SbINV2, was studied, and a strong negative correlation of SbINV2 to stem sucrose content was observed. This reveals a possibility of involvement of vacuolar invertase gene, SbINV2, in sugar accumulation in sweet sorghum stems, and as a key candidate for molecular breeding studies for higher stem sugar content.  相似文献   
56.
在中国现代文学运动发展史上,《红高粱家族》的出现具有审美转型的深刻意义。作者用“虚构叙事”取代“亲历在场”,用“酒色财气”颠覆“英雄崇拜”,用“灵魂救赎”挑战“旧梦新知”,并以强烈的艺术理性精神,宣告了革命英雄传奇神话的历史终结。  相似文献   
57.
报道了《河北植物志》与《河北高等植物名录》未记录的植物1属3种1变种。其中拔毒散(Sida szechuen-sis Matsuda)、偃狗尾草[Setaria viridis(L.)Beauv. var. depressa(Honda)Kitag.]在河北省首次记录。  相似文献   
58.
Radioactively labeled iron (59Fe) was used to study differential uptake in sorghum plants in the recovery stage of chlorosis. Radio-labeled 59Fe was supplied through root feeding in nutrient solution experiment (48 hrs, pH 6.2) to non-chlorotic and chlorotic plants. Chlorotic plants were further treated with foliar spray [ferrous sulfate (FeSO4), FeSO4 + thiourea (TU), FeSO4 + citric acid (CA), FeSO4 + thioglycollic acid (TGA)] to study the uptake of radio-labeled 59Fe through root feeding during recovery process of chlorosis. Under iron deficiency, the differential uptake of 59Fe was markedly increased in leaves and stem of chlorotic control (-Fe) sorghum plants as compared to non-chlorotic control (+Fe) and foliar sprayed (FeSO4, FeSO4 + TU, FeSO4 + CA, and FeSO4 + TGA) plants. The lowest uptake of 59Fe was observed in younger leaves (24.33 nmol, g?1 fresh weight h?1) and stem (1.98 nmol, g?1 fresh weight h?1) of non-chlorotic control followed by foliar sprayed plants in comparison to chlorotic control, respectively. Similarly less 59Fe uptake was observed in the older leaves of FeSO4 + CA sprayed (21.70 nmol, g?1 fresh weight h?1) plants in comparison to chlorotic control (35.60 nmol, g?1 fresh weight h?1). The highest differential 59Fe uptake through nutrient medium was in the roots of plants, which were foliar sprayed with FeSO4 along with TU. The role of iron alone and along with citric acid and thiol compounds is discussed in recovery of chlorosis.  相似文献   
59.
高粱茎尖和幼穗细胞悬浮系的建立   总被引:1,自引:1,他引:1       下载免费PDF全文
建立有效可靠的细胞悬浮培养方法对进一步开展原生质体培养和转基因研究具有重要意义。本研究以茎尖和幼穗作为外植体,采用愈伤振荡培养法、匀浆收集培养法和直接培养法三种方法进行了细胞悬浮系建立的方法研究。结果表明:与茎尖相比,幼穗是更适宜开展高粱细胞悬浮培养的理性外植体。采用三种培养方法均可建立幼穗细胞悬浮系,其中幼穗愈伤振荡培养法最为稳定可靠,幼穗匀浆收集培养法和直接培养法的稳定性稍差,但获得的细胞悬浮系生长状态较好,有利于进一步开展增殖继代培养。结果还表明,茎尖愈伤振荡培养法也是一种稳定可靠的细胞悬浮系制备方法,但茎尖匀浆收集培养法稳定性稍差,而直接培养法效果最差不宜采用。  相似文献   
60.
种植方式与种植密度对大力士高粱的影响   总被引:1,自引:0,他引:1  
本试验用裂区设计,研究了大力士高粱在16种不同种植密度、3种种植方式下,产草量、生产速度、茎叶比、茎粗的变化情况。结果表明,在撒播密度为18 kg/hm2、条播为22.5 kg/hm2、穴播为28.5 kg/hm2时达到最高产量;生长速度在第53-55 d时最高,达5.7 cm/d;茎叶比随着产量的增加逐渐减少;茎粗随着种植密度的增大而有减小的趋势。  相似文献   
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