Fasciation in chickpea: genetics and evaluation

Summary A spontaneous fasciated mutant was detected in the chickpea cv. Amethyst. It was characterised by broad, strap-like stems, irregular leaf arrangement and clustering of pods towards the stem apices. F₂ and F₃ segregations showed that fasciation was controlled by a single, recessive gene for which the symbol fas is proposed. Field trials comparing the fasciated mutant with its non-fasciated isoline showed that fasciation was associated with lower yield, larger seeds, delayed flowering and increased lodging.     

感染国槐带化病植株内源激素及转录组分析

[目的]为探究国槐带化病的致病机理,进而为国槐带化病的防治研究提供理论依据.?[方法]以国槐健康与感病枝条作为研究材料,对其生长期间的5、8、9及11月份中枝条生长素、玉米素、赤霉素和脱落酸含量进行连续测定,通过选取8月份国槐的病、健组织进行转录组测序筛选差异表达基因,并进行qPCR验证分析.?[结果]在5、8、9、1...     

Research on the inheritance of fasciation in lettuce (Lactuca sativa L.)

Summary Inheritance of fasciation was investigated in reciprocal crosses between two lettuce varieties: Suzan (non-fasciated) and Noran (fasciated). In glasshouses parental plants, F₁, F₂, and F₃ populations were assessed for fasciation according to a scale from 0 (non-fasciated)-9 (extremely fasciated).The observed environmental variation for fasciation of the homozygous parents was very low or absent, but the environmental variation for the F₁ populations was large. On the basis of this large variation of the heterozygous F₁ plants we supposed that such a variation also occurred in F₂ and F₃ populations.Considerable mortality was observed in all generations, which supposedly occurred at random in parents and F₁ but was non-random in the segregating F₂ and F₃ populations. So, means and variances of F₂ populations will be biased and therefore they were not used for genetical analyses of fasciation.From F₁ and F₃ populations and from some F₂ populations it appeared that no differences occurred between reciprocals. The differences for fasciation between reciprocal F₂ populations in the 1977 A experiment may result from non-random plant survival. A regression of F₃-means on the values for fasciation of parental F₂ plants, adjusted for their inbreeding, resulted in a realized h²-narrow of 0.4. This indicates that in the surviving plants of the F₂ populations still additive genetic variation was present to select successfully for non-fasciated plants.     

柿树带化和刺槐丛枝的PCR检测

根据植物菌原体１６ＳｒＲＮＡ基因序列,合成一对寡核苷酸引物,用ＳＤＳ ＣＴＡＢ改进法直接提取田间发病的柿树带化病、刺槐丛枝病树和健康树皮层的ＤＮＡ,用ＰＣＲ方法成功地从病树ＤＮＡ模板中扩增出约１．１７ｋｂ的特异产物,经酶切进一步证实为植物菌原体１６ＳｒＤＮＡ．此项研究表明用特异合成的引物Ｆ１６／Ｒ１６,经ＰＣＲ扩增可以快速灵敏地检测植物菌原体．     

Allelic relationship between spontaneous and induced mutant genes for stem fasciation in chickpea

Stem fasciation is a morphological abnormality observed in plants where the stem is widened and leaves and flowers or pods are clustered at the apex. Several spontaneous mutants and one induced mutant for stem fasciation are found in chickpea (Cicer arietinum L.). This study was aimed at determining allelic relationship between spontaneous and induced mutant genes controlling stem fasciation and effects of stem fasciation on grain yield. Two spontaneous (ICC 2042 and ICC 5645) and one induced (JGM 2) stem fasciation mutants were crossed in all combinations, excluding reciprocals. The F₁ and F₂ plants from a cross between the two spontaneous mutants had fasciated stem. This indicated the presence of a common gene (designated fas1) for stem fasciation in the two spontaneous mutants. The F₁s of the crosses of the induced mutant JGM 2 with both spontaneous mutants had normal plants and segregated in a ratio of 9 normal : 7 fasciated plants in F₂. Thus, the gene for stem fasciation in the induced mutant JGM 2 (designated fas2) is not allelic to the common gene for stem fasciation in spontaneous mutants. The two genes in dominant condition produced normal non‐fasciated stem. The fasciated and the non‐fasciated F₂ plants did not differ significantly for number of pods per plant, number of seeds per plant, grain yield per plant and seed size, suggesting that it is possible to exploit the fasciated trait in chickpea breeding without compromising on yield.     

景观植物槲寄生的寄主树种及数量分布特点

对张广才岭西北麓次生林内槲寄生的寄主树种和数量分布状况进行了调查分析。结果表明,张广才岭次生林中槲寄生的主要寄主树种为杨树、椴树和榆树,其他树种很少;单株簇生是槲寄生的主要着生方式,2,3,4和5株簇生有一定数量,6株以上簇生的已经微乎其微;槲寄生主要着生在寄主树体的上、中部和侧枝上,不同树种的表现不尽相同;阳坡、坡下部、平坡和农田边的次生林中槲寄生的数量相对较多。       

Maize participatory breeding in Portugal: Comparison of farmer's and breeder's on‐farm selection

“VASO” is a Portuguese participatory maize breeding project (1984), where several maize landraces such as “Pigarro” have been selected both by a farmer's (phenotypic recurrent selection) and a breeder's approach (S2 lines recurrent selection). The objectives of this study were to determine the phenotypic and genotypic responses to participatory selection using these two different approaches, to clarify to which extent both selection methods preserve genetic diversity, and conclude what is the preferred method to apply in sustainable farming systems. The results, obtained via ANOVA, regression analyses and molecular markers, indicate that for both selection methods, genetic diversity was not significantly reduced, even with the most intensive breeder's selection. Although there were some common outputs, such as the determinated versus indeterminated ears, cob and ear weight ratio per ear and rachis 2, specific phenotypic traits evolved in opposite directions between the two selection approaches. Yield increase was only detected during farmer selection, indicating its interest on PPB. Candidate genes were identified for a few of the traits under selection as potential functional markers in participatory plant breeding.