Some observations on the origin and evolution of the winged bean (Psophocarpus tetragonolobus)

Summary On the basis of phytogeographic evidence it is suggested that Psophocarpus tetragonolobus has an African ancestry, a possible parallel with the origin of guar (Cyamopsis tetragonoloba) is suggested. The most probable ancestral species is Ps. grandiflorus native to East Africa from Ethiopia to Zaire. This hypothesis could be tested by experimental hybridization between the cultigen and its closest wild relative Ps. grandiflorus.     

红小豆种质资源子粒色泽及出沙率的遗传变异

对我国主产区红小豆地方品种资源中随机抽取的335份、日本25份和韩国2份材料子粒色泽和出沙率进行了鉴定评价。结果表明，红小豆粒色红度值（a^＊）平均为19．71，粒色偏灰暗，变幅为13．0—26．0；黄度值（b^＊）平均为9．58，变幅为5．2-16．8；亮度值（L^＊）平均为26．47，变幅为18．1—34．0；出沙率平均值为68．08％，变幅为61．90％-75．98％；地区间显示出明显差异。a^＊、b^＊、L^＊和出沙率4个性状均具有较高的遗传变异，但粒色a^＊、b^＊和L^＊的广义遗传力值h^2较高，出沙率的广义遗传力较低。筛选出红度值超过24．0的种质资源6份，筛选出亮度值超过30．0的种质资源16份，筛选出黄度值超过13．0的种质资源8份，筛选出出沙率高于73．5％资源8份。     

Variation in virulence and resistance in the bean-bean rust pathosystem in Ecuador

Twenty two Uromyces appendiculatus isolates were tested on 20 differential and 25 Ecuadorian Phaseolus vulgaris cultivars in the seedling stage. Based on the infection types 20 races could be discerned. The Ecuadorian cultivars differed greatly in their reaction to the isolates, from resistant to only one isolate (`Red Small Garden') to resistant to all isolates (’G2333‘). The isolates showed a wide range of virulence to the Ecuadorian cultivars, from virulent to only two cultivars (isolate 13) to virulent to 21 cultivars (isolates 5 and 23). Seven cultivars with a basically susceptible infection type appeared to differ greatly in quantitative resistance when tested in three consecutive crop cycles. The disease severities in percentage leaf area affected averaged over the three cycles ranged between 83.9% for ‘Red Small Garden’ and 13.1% for ‘INIAP-414’. Race-specific resistance does not seem an advisable breeding strategy, but the quantitative resistance offers a good alternative.     

Inheritance of resistance to angular leaf spot (Isariopsis griseola Sacc.) in french bean (Phaseolus vulgaris L.)

Summary Angular leaf spot (Isariopsis griseola Sacc.) is a serious disease of French bean in the hills of India and 40 to 70 per cent of the green pods are damaged and rendered unmarketable. Crosses were made between PLB 257, (Phaseolus coccineus L.), a red flowering pole tope, resistant to angular leaf spot, and Contender (Phaseolus vulgaris L.), a highly susceptible commercial cultivar. Studies of the F₁, F₂, and F₃ progenies indicated that PLB 257, carries a recessive gene imparting resistance to angular leaf spot.     

Symbiotic variability in Vicia faba. 3. Genetic effects of host plant,rhizobium strain and of host × strain interaction

Summary Six Vicia faba populations were grown in all possible combinations with six Rhizobium leguminosarum strains in order to estimate the relative importance of the three genetic components of symbiotic variability. Additive genetic effects of host genotype and rhizobium genotype accounted for only 8.9% and 11.8% of the total phenotypic variation. Non-additive variation attriabutable to specific host genotype × rhizobium genotype interactions was by far the largest component of variation and accounted for 73.8% of phenotypic differences. Therefore the greatest improvement in symbiotic nitrogen fixation is likely to arise from simultaneous selection of both symbionts.     

Evaluation and utilisation of cacao (Theobroma cacao L.) germplasm at the International Cocoa Genebank, Trinidad

The aim of this study was to identify promising genotypes in the International Cocoa Gene bank, Trinidad (ICG,T) for use in cacao breeding. Subsets of the germ plasm collection were evaluated for bean number, bean weight, pod index (581 genotypes) and resistance to Phytophthora pod rot(500 genotypes). Among three groups of cacao assessed (For astero, Refractario and Trinitario), Trinitario had the highest percentage of genotypes (36.9%) with large bean weight (> 1.2 g), while For astero possessed the highest proportion of genotypes (22.6%) with a large number of beans (> 45). The ICS population had the highest percentage (44.1%) of genotypes with heavy beans, and IMC the highest percentage of genotypes with large bean number (68.6%). A low, but significant negative correlation (r = –0.19, p≤ 0.001) between bean number and bean weight suggests that an increase in bean number may repress an increase in bean weight and vice versa. However, inten genotypes good values of bean weight and number were combined demonstrating that selection for both large bean number and bean weight is possible. The highest percentage (28.1%) of genotypes with low pod index (< 20.1) was observed in the Trinitario group (mainly ICS). The Forastero group had the highest percentage of Phytophthora resistant accessions(18.0%). The PA population had the highest proportion of resistant (24.0%) and moderately resistant (38.0%)genotypes. Sixty-five and 99 genotypes were categorised with large bean weight and high bean number, respectively, and 60 genotypes were found with a low pod index. Seventy-eight genotypes were identified with resistance to Phytophthora podrot. A significant relationship was observed between resistance to Phytophthora pod rot (measured as the frequency of localised lesions) and bean number (r = –0.45, p ≤ 0.001)showing that the two traits may complement each other. The combination of low to intermediate pod index with moderate to high resistance to Phytophthora podrot was found in 87 genotypes, 12 of which were also reported to have resistance to witches’ broom disease. These genotypes are of high potential value in cacao breeding and their inclusion in working and corecollections would be justified. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inheritance of temperature sensitivity of the photoperiod response in common bean (Phaseolus vulgaris L.)

Summary Photoperiod response of flowering in common bean (Phaseolus vulgaris L.) is thought to be controlled by the genes Ppd and Hr. However, cultivars also vary in the degree that cooler temperatures reduces their sensitivity to photoperiod. To examine the inheritance of this temperature sensitivity, crosses of cvs. Gordo x de Celaya and Flor de Mayo × Rojo 70 were evaluated at two sites differing in mean temperature and using 12.5-h natural photoperiod or 18-h artificially extended photoperiod. Under 18-h photoperiod at the warmer site, Palmira, no plants of the parents or of the F₂ populations flowered, confirming that the parents were sensitive to photoperiod. Under 12.5-h photoperiod at the cooler site, Popayan, the parents for each cross flowered at similar dates and no segregation for days to flower was observed. However, under 18-h photoperiod, de Celaya and Rojo 70 and the F₁ populations did not flower within 100 days after planting, while the F₂ and F₃ populations showed segregation that was consistent with single gene inheritance, late flowering being dominant. Late flowering at Popayan under 18-h photoperiod indicates a lack of temperature sensitivity, so temperature insensitivity of the photoperiod response was dominant to sensitivity. The name Tip, for temperature insensitivity of photoperiod response, is proposed for this gene, with the recessive form of this gene conditioning earlier flowering at cooler temperatures with long daylengths. It is recognized that the observed segregation patterns could represent the effect of multiple alleles at the Ppd or Hr loci, and studies are proposed to test this possibility with molecular markers and recombinant inbred lines.     

高含水率刀豆、茄子和青椒的等温解吸规律

对高含水率刀豆(普通浓度、高浓度预处理和未预处理)、茄子和青椒(普通浓度预处理)进行了静态下平衡含水率(EMC)的测定试验(在40℃、60℃和80℃的解吸环境温度,5％～88％的相对湿度下),得出了其反映平衡含水率与温湿度关系的等温解吸曲线,讨论了温湿度、预处理及种类对平衡含水率影响的规律。并对普通浓度预处理刀豆选择了最适宜的平衡含水率模型;EMC=[(1n(1-RH))/(-aT)]~(1/b),确定了其模型系数为:a=0.63,b=2.77。     

玉米酸豆奶的研制

该文对玉米酸豆奶的加工工艺进行探讨，用玉米糖化产物作为乳酸菌发酵基质，采用正交试验设计确定了玉米酸豆奶的主要工艺因素：豆奶与玉米浆配比为70∶30，发酵温度42℃，发酵时间6 h，保加利亚乳杆菌∶嗜热链球菌为1∶2；选择加入稳定剂解决玉米酸豆奶杀菌时产生的分层现象；对乳酸菌进行驯化，以适合在豆奶中生长。     

豆腐乳感官和理化品质的主成分分析

对市售的16种豆腐乳利用感官评定和理化分析结果进行主成分分析和综合评价,结果表明,感官评判的前4个主成分可以解释豆腐乳感官品质的85.25%,前4个主成分的贡献率分别为49.60%,16.76%,12.05%,6.87%;理化成分的前4个主成分可以解释豆腐乳理化特性的79.02%,前4个主成分的贡献率分别为32.68%,21.33%,17.82%,7.20%。利用感官评分和理化特性的主成分分析结果,分别对所取样品进行了综合评分