Morphological variation in Astragalus hamosus L. and Coronilla scorpioides L. populations of Tunisia

Morphological variation between Astragalus hamosus and Coronillascorpioides populations was studied using local germoplasm collected in northern and central Tunisia. Twenty-one morphological traits were recorded and data were analysed using complementary statistical analysis. Considerable variation based on morphological and agronomical traits was found between populations and for both species. Pod and peduncle lengths as well as flowers number were the most discriminant variables between populations. Differences were also found for variables like seed number per pod, seed yield and dry matter production. Significant correlations were found between plant traits and the environmental parameters of the origin sites. This study revealed enough variation among populations to initiate a selection programme for pasture improvement in arid and semi-arid areas of Tunisia, where the two species are well adapted. This revised version was published online in July 2006 with corrections to the Cover Date.     

Morphological variation within a sour cherry collection

Summary Morphological traits of 28 full-sib sour cherry (Prunus cerasus L.) families developed with pollen from European sour cherry selections were evaluated with principal component (PC) analysis. The traits which loaded on the first PC were size characters such as lateral length, leaf area, fruit weight, and trunk diameter increase. These character loading on the first PC could be interpreted as representing gradations between morphologies characteristic of the 2 presumed progenitor species, sweet cherry (P. avium L.) and ground cherry (P. fruticosa Pall.). Mean family differences in trunk diameter increase, lateral length, leaf area, and fruit weight varied approximately 12, 3.7, 2.5, and 2 fold, respectively. These results suggest that it may be possible to select sour cherry hybrids approaching the tree and fruit size of either progenitor species. The results are discussed in reference to germplasm collection and the potential of certain cultivars and hybrids as parents.     

The Use of Multivariate Analyses to Eliminate Redundant Variables when Evaluating Potatoes for Chip Quality

Selection for good chipping clones in potato breeding often takes place during the middle and late selection stages. This is due to the considerable resources needed for the assessment of several characteristics. Objective multivariate methods for the elimination of redundant variables were applied to eight standardized chipping quality traits recorded on advanced clones over 15 years at two locations in New Brunswick, Canada. The clones were evaluated of specific gravity and the following chipping scores: direct from the field in August; after 10 days storage at 13 °C; from 4 °C storage in February; from 4 °C storage in February with 1 week, 2 weeks, 3 weeks and 4 weeks reconditioning at 16 °C. Five elimination methods produced a similar deletion order. In every subset obtained, specific gravity and direct chipping from the field were always retained. Reconditioning treatments from one to four weeks after cold storage were shown to be the most redundant. The reduction in the number of traits from eight to four by every technique could recover more than 80 % of the original variation, showing that redundant variables were effectively discarded.     

Evaluation of an Italian germplasm collection of Festuca arundinacea Schreb. through a multivariate analysis

Summary Forty-eight accessions of tall fescue (Festuca arundinacea Schreb.), collected from Northern to Southern Italy, were analyzed using both univariate and multivariate analysis applied to a set of 12 quantitative traits. Four principal components were found to explain 77% of the total variation in the dependence structure. Productivity characters together with heading time and dimensions of flag leaf appeared to be the major sources of diversity among tall fescue populations. On the basis of the 4 principal components similar populations were clustered according to minimal distance analysis. Seven clusters were identified. The results of cluster analysis confirmed the presence of a remarkable diversity within the germplasm collection and explained why results of a univariate analysis of variance did not reveal significant differences among groups of accessions collected in Northern, Central and Southern Italy. The multivariate approach seemed to point out a problem of genetic erosion of the local germplasm in the Po Valley (Northern Italy) and, on the whole, appeared to be a valid system for tall fescue germplasm evaluation.Research supported by C.N.R., Italy, special grant I.P.R.A., Subject 1.5.1., paper n. 1146.     

Characterization of six varieties of Cucumis melo L. based on morphological and physiological characters, including shelf-life of fruit

Seventy-two accessions covering six varieties of Cucumis melo were characterized by using 35 morphological characters with emphasis on shelf-life, and the relationships between shelf-life and related characters was investigated. Principal component analysis (PCA) revealed that development period of plant and fruit, size of seed and fruit, shelf-life, stem hair, flesh juiciness, netting, abscission of peduncle, rapid yellowing of epidermis at maturity, Brix value, and color of flesh and epidermis etc. were the principal characters to discriminate melon accessions examined in the present study. According to the scatter diagram, vars. acidulusand makuwa, both of which belong to the Oriental melon, are closely related because of their short growth duration, small seed, thin pericarp and poor shelf-life, while American cantaloupe (var.reticulatus) and European cantaloupe (var. cantalupensis) are rather closely related due to their climacteric fruit with orange flesh, slipped peduncle and rapid yellowing of epidermis at maturity, which is closely related with their shelf-life. PCA also indicated that var. saccharinus was closer to var. inodorus than to the other varieties, due to their requirement of long period for development, large size of seed and fruit, and half- or non-slipped peduncle. Shelf-life of melon fruit was significantly correlated with the following characters: quality of flesh, size of seed and fruit, abscission of peduncle, development periods of plant and fruit, rapid yellowing of epidermis at maturity, Brix value and color of flesh and epidermis. Accessions with good shelf-life were mostly found in vars. saccharinus and inodorus. This revised version was published online in July 2006 with corrections to the Cover Date.     

Levels of host plant resistance to banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), in African Musa germplasm

Forty-five Musa clones, including endemic and introduced cultivars plus hybrids, were evaluated for resistance against the banana weevil, Cosmopolites sordidus, in a field trial in Uganda. The predominant groups of staple crops, East African highland bananas (Musa spp. AAA) and plantains (Musaspp. AAB), as well as plantain-derived hybrids (AAB × AA), showed the highest levels of susceptibility to this pest. These were followed by dessert bananas (Musa spp. AAA), exotic bananas (Musa spp. ABB) and finally diploids of M. acuminata (AA). Hybrids of banana origin were highly resistant. Some East African highland cultivars, especially brewing types (e.g., Kabula, Bagandeseza, Ediirira), showed intermediate levels of resistance. Among the non-highland bananas, high levels of resistance were observed in Yangambi-Km5 (AAA), Cavendish (AAA), Gros Michel (AAA), Kayinja (ABB, Pisang Awak subgroup), Ndiizi (AB, Ney Poovan subgroup)and Kisubi (Ney Poovan subgroup). The highest resistance was observed in banana hybrids TMB2×7197-2, TMB2×8075-7 and the wild banana Calcutta-4 (AA). These were considered the best sources of resistance for a weevil resistance-breeding programme with the two hybrids commonly used as improved male parents. This revised version was published online in July 2006 with corrections to the Cover Date.     

A factor analysis of plant variables associated with architecture and seed size in dry bean

Summary A knowledge of the biological and functional relationships among traits would be of benefit to plant breeders in the choice of traits to use for increasing efficiency of selection in a breeding program. Principal factor analysis was used to identify biological and functional relationships among dry bean (Phaseolus vulgaris L.) traits in segregating populations of a phenotypic recurrent selection program designed to introduce upright architecture into medium-sized dry bean.Two biological interpretations were assigned to factors extracted in the analysis of four seed/pod traits. The first was a size factor, loaded with seed weight and pod width, and the second a number factor, which was loaded with number of seeds per pod and pod length. Similarly, three factors were extracted from the analysis of fifteen architectural traits. The first factor was interpreted as an elongation factor, and was loaded with internode length measurements, while the second factor was interpreted as a structural factor, and was further divided into two subclasses namely, sturdiness factor and profile factor. The sturdiness factor comprised hypocotyl diameter and hypocotyl length, while the profile factor comprised branch angle and number of basal branches. The third factor which was called a reproductive factor was loaded with pod distribution traits and the number and location of nodes on which pods were borne.     

黄土高原治理中的委托—代理关系及激励机制

根据委托—代理理论 ,对黄土高原治理中的参与方进行了辨析。分析了现存的委托—代理关系中存在的问题 ,设计出了新的激励与约束机制 ,使代理人能够按照委托人的意志行事     

Optimization of Farmyard Manure to Substitute Mineral Fertilizer for Sustainable Productivity and Higher Carbon Sequestration Potential and Profitability under Gardenpea-French Bean Cropping System in the Indian Himalayas

Carbon sequestration potential (CSP) and sustainability of gardenpea-french bean cropping system was assessed with farmyard manure (FYM) application vis-à-vis mineral fertilization as recommended NPK (NPK) and integrated nutrient management practices (INM) after six years’ cropping in Indian Himalayas. Application of 20 tons FYM ha^?1 provided highest CSP (0.527 Mg C ha^?1 year^?1) in soil and sustainability index. With the help of quadratic equations, it was estimated that maximum profit (optimum yield) and turn over of invested money could be achieved with application of 20.0 and 15.6 t FYM ha^?1, respectively. Application of 5.9 and 8.9 tons FYM ha^?1 would substitute NPK and INM, respectively. Pod number plant^?1 was the most important yield-contributing attribute as found from principal component analysis. Pod yield could be modelled through multiple linear equation with help of yield attributes.     

An in vivo analysis of the therapeutic and synergistic properties of Chinese medicinal formula Yin-Chen-Hao-Tang based on its active constituents

6,7-Dimethylesculetin (D), geniposide (G) and rhein (R) are the three major active ingredients of Yin-Chen-Hao-Tang (YCHT), a famous Chinese herbal formula, which has been shown to be clinically effective for treating hepatic injury (HI) syndrome. The present study was conducted to investigate the therapeutic and synergistic effects of COC (combination of D, G and R) on HI rats by combining pharmacokinetic with biochemical analysis strategy. Plasma was analyzed by using reversed-phase high performance liquid chromatography (RP-HPLC). Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) models were built to evaluate the therapeutic and synergistic effects of COC at the biochemical level. Here, we report that the COC combination could increase the plasma level, slow elimination rate, exert a more robust therapeutic effect than any one or two of the three individual compounds by hitting multiple targets in a rat model of HI. Overall, this beneficially accounts for the popular view that traditional Chinese medicine (TCM) formula usually takes multi-component to exert their therapeutic effects. We suggest that dissecting the mode of action of clinically effective formula to be capable of producing a sufficient effect at low doses.