Patterns of diversity in pigeonpea (<Emphasis Type="Italic">Cajanus cajan</Emphasis> (L.) Millsp.) germplasm collected from different elevations in Kenya

Pigeonpea germplasm accessions collected from low (<500 m), medium (501–1000 m), high (1001–1500 m) and very high elevation zones (>1500 m) of Kenya were evaluated for 15 agronomic traits and seed protein content at ICRISAT, Patancheru, India. There were significant differences (P < 0.001) among elevation zones for the number of primary and secondary branches, days to 75% maturity, pod length, seeds per pod, 100-seed weight and seed yield. Mean values indicated that the accessions from low elevation zone were significantly different from those collected in higher elevation zones for early flowering and maturity, number of primary branches, pod length, number of pods per plant, seeds per pod, 100-seed weight, seed yield and harvest index. None of the accessions collected in Kenya belonged to extra early (<80 days to 50% flowering) and early (80–100 days to 50% flowering) maturity groups, as defined by time to flowering at Patancheru, India. Mean diversity index based on all characters indicated that accessions from the low elevation zone are more diverse than those from the higher elevation zones. Frequency distribution for trait extremes indicated that the accessions from the low elevation zone were early to flower and mature, short statured, produced more primary and secondary branches with high pod bearing length, long pods, more pods per plant, more seeds per pod, a high seed yield and harvest index. Accessions from the very high elevation zone were late flowering, with a large number of tertiary branches, large seeds and a high shelling percentage and could be a source for cold tolerance and the breeding of vegetable types. Results suggest that the elevation of collection sites is therefore a very important determinant of variation patterns of pigeonpea in Kenya.     

Agrobiodiversity of eleven accessions of <Emphasis Type="Italic">Mucuna pruriens</Emphasis> (L.) DC. var. <Emphasis Type="Italic">utilis</Emphasis> (Wall. ex Wight) Baker ex Burck (velvet bean) collected from four districts of South India

Eleven accessions of an under-utilized legume, Mucuna pruriens (L.) DC. var. utilis (Wall. ex Wight) Baker ex Burck (velvet bean) were collected from four districts of South India and their agronomic characters were evaluated. The vegetative growth characters such as the germination percentage, plant height, number of leaves and branches per plant were recorded. The yield based characters such as the number of clusters/plant (4–14), number of flowers/cluster (3–15) and the fertility index (66–91%) were observed. The seed yield reaches 2.9–6.9 t/ha. The number of seeds per pod, seed weight and the seed recovery percentage were also calculated. The level of diversity in the agrobotanical traits of velvet bean observed in the present study could be of interest in a breeding programme.     

Compound inflorescence cardamom (Elettaria cardamomum (L.) Maton) in India

Cardamom (Elettaria cardamomum (L.) Maton) is an important spice crop of India and valued for its dried capsules. Regular surveys are being undertaken by Indian Institute of Spices Research (IISR), Appangala, Karnataka, India for collecting the variable germplasm of cardamom. At present 436 cardamom accessions collected from cardamom growing tracts of South India are conserved in field gene bank. Among the collections, 23 accessions with varied branching pattern were assembled during explorations and characterized for 16 plant, panicle and capsule characters during 2003–2005. The coefficient of variation was greatest for yield per plant (77.94%) followed by branches per panicle (49.40%) and minimum for dry recovery per cent (7.73%). Two accessions, IC 547214 and IC 349544 were identified as promising with desirable yield contributing characters. The accessions, IC 349553 with extensive branching at the proximal end of the panicle and IC 547180 with dark green capsules even after drying were found to be unique. All the characterized accessions are maintained under ex situ cardamom gene bank of IISR.     

Genetic diversity in West African okra (Abelmoschus caillei) (A. Chev.) Stevels — Multivariate analysis of morphological and agronomic characteristics

Summary Factor, Principal component and canonical analyses were used to study the extent of genetic diversity among 30 accessions of West African okra. Genetic variability among the accessions proved to be large. Pigmentation of various parts of the accessions and fruit characteristics contributed significantly to the total variation observed. Factor analysis and principal component analysis produced similar results which were substantially different from those produced by canonical analysis. The first three canonical variables accounted for 100% of the total variance while the number of pods per plant, and pod weight primarily accounted for the first canonical variable. Whereas the second canonical variable was primarily loaded by number of seeds per pod and fruit colour, the third canonical variable was comprised of a weight of 100 seeds and number of epicalyx segments.The level of variability observed supports the opinion (Stevels, 1988, 1990) that this okra type constitutes a separate species.     

Autofertility in a pure line faba bean (Vicia faba L.) germplasm collection

Summary A pure line faba bean germplasm collection (BPL) was derived by a process of cyclic single plant progenies starting in 1979 through 1985. In 1985/86, 840 of these pure line accessions from 677 original populations from 41 countries were evaluated for autofertility by comparing the mean of five plants where all flowers were tripped vs. five plants with no tripped flowers for number of seeds produced (seed index). In a replicated trial grown at the same time, seed yield, 100 seed weight, number of pods per plant, seeds per pod, and number of flowers per inflorescence were also evaluated. A high number of BPL accessions failed to set seeds in the screen houses without tripping, the mean seed index measure of autofertility was 0.51 with a C.V. of 74.2%. There were marked differences among countries of origin for autofertility, with Egypt having the highest (SI = 0.94) and the USSR the lowest (SI = 0.26) autofertility, however, most countries expressed a large range, suggesting that breeders should first look in their own material for this trait rather than searching in exotic germplasm. In general, there was a higher level of autofertility in Middle Eastern countries that may be due to natural selection for non-dependency on pollinators for high yield. Contrary to the findings of others, large seeded accessions had a high autofertility (SI = 0.704) compared to small seeded accessions (SI = 0.384), however, both had similar ranges. In general, there was no significant correlations among autofertility and yield and its components. The variability found in this large pure line collection for autofertility is of potential use for developing cultivars not dependent on insect populations for high yield and for developing self-pollinated faba bean.     

Biodiversity of common bean (Phaseolus vulgaris L.) in Honduras, evidenced by morphological characterization

This paper describes findings in the characterization of 300 accessions in a collection of common beans (Phaseolus vulgaris L.) in Honduras. The plant material was collected from 1990 to 1994 (4 years before the damaging Mitch Hurricane) covering most of the Departments of the country and kept at the Escuela Agrícola Panamericana Zamorano. Thirty-two morpho-agronomical characters were evaluated and the results were grouped by classes. The studied accessions showed a marked diversity with high predominance of red and small seeds. The accessions with purple flowers had black seeds and originate mainly from the western area of the country where this type of seed is preferred. Principal Component Analysis shows that clearly defined groups do not exist. The conservation of this diversity is recommended for future propagation, breeding and the investigation of the genetic relationships and other studies.     

Diversity in White Lupin (<Emphasis Type="Italic">Lupinus albus</Emphasis> L.) Landraces from Northwest Iberianplateau

All the accessions (35) of white lupin (Lupinus albus L.) landraces collected from northwest Iberian plateau and maintained at the Spanish germplasm collection (CRF of INIA), were studied with the general objective of assessing the biodiversity of these landraces and to ascertain their value as genetic resources for the development of germplasm adapted to the areas where they were collected with long and chilly winters. The characterization study comprised 51 qualitative and 50 quantitative characters. Quantitative parameters were analyzed by Principal Components Analysis (PCA). The 2-dimensional plot (49.3% of cumulative variability) formed a main group of accessions and 4 outliers (#1, #9, #27 and #28) separated in the first PC. The characters with a higher contribution to the first PC were inflorescence length, leaf petiole length and leaf central foliole area. The presence of alkaloids, the percentage of plants killed by soil borne fungal diseases, the phenology, the yield per plant and yield components were also assessed. Twenty six accessions (the main group in the PCA plot) showed high homogeneity, with the following highlights: bitterness, indeterminate growth habit, early ripeness and spring sowing with the exception of #18, in which seeding date is unknown and it had a later phenology. By contrast accessions #9 and #27 were bitter of autumn sowing with determinate growing habit and they had the longest values of primary inflorescence length and a later phenology when they were sown in spring. Average values for yield and yield components showed a broad range of variation between accessions. The main yield component was the number of pods per plant. Accession #22 had the highest mean seed mass, although this had not significant influence in yield. Accession #17 showed the highest yield and #1 the lowest. This last also had the lowest values of inflorescence length, leaf petiole length and leaf central foliole area. No significant differences of resistance to soil-borne fungi were found between accessions. The year had a significant effect in the phenology, yield and yield components except for number of seeds per pod. The studied material might be of interest for the development of spring sowing germplasm adapted to north Iberian peninsula.     

Diversity in Indian sesame collection and stratification of germplasm accessions in different diversity groups

Sesame (Sesamum indicum L.) is one of the ancient oil crops, grown in India since over 5,000 years ago. Diversity in the Indian sesame collection (3,129 accessions), representing all eco-geographical regions, for a range of morphological and agronomic characters was studied. Wide variation in plant habit (plant height and branching pattern), pubescence of various plant parts (stem, leaf, corolla and capsule), flower colour and number of flowers per leaf axil, capsule characteristics (shape, size, number in the axil of a leaf and number of locules in a capsule), number of capsules per plant, number of seeds per capsule, mean seed weight, and yield per plant was recorded. A detailed multivariate analysis was performed on a set of 100 selected accessions representing different agro-ecological zones. The accessions were classified into 7 discrete clusters. The principal components analysis described the spatial relationship among the entities and confirmed groupings obtained through clustering. Based on the clustering pattern of 100 accessions, the entire collection was allocated to different clusters. Representation of various zones in 7 clusters gives us the opportunity to form distinct diversity groups making combined use of passport and characterisation data. These diversity groups would subsequently be used for sampling the accessions for building up a core collection of sesame, a project already operative at the NBPGR.     

Phenotypic diversity of durum wheat (<Emphasis Type="Italic">Triticum durum</Emphasis> Desf.) from Jordan

Durum wheat landrace genotypes are disappearing from the main wheat areas in Jordan, because of spreading of new uniform cultivars and the serious reduction in wheat cultivation. This study was conducted to evaluate genetic diversity in durum wheat landraces from Jordan and to identify desirable agronomic traits. Landraces were collected from two target areas: Ajloun and Karak. The collected material was grown under rainfed conditions using an augmented design with five blocks and four repeated check cultivars. Data were collected for 14 morphological and agronomic traits. Phenotypic diversity index (H′) was estimated, and the relationships among accessions were measured using cluster analysis and dendrogram similarity matrix. The results revealed the presence of a wide range of variability among landraces., which possess high levels of variability for biological yield, fertile tillers, number of seeds per spike, seed weight per spike and weight of 1000 seeds. These landraces must be considered as a reservoir of genes that plant breeders need in their wheat improvement programs and should be conserved both ex situ and in situ.     

Diversity Analysis of Garlic (Allium sativum L.) Germplasms Available in Nepal Based on Morphological Characters

A total of 179 garlic (Allium sativum L.) accessions were collected from various parts of Nepal in 2000. Each accession was planted in each of a plot of 2.25 m² at the Institute of Agriculture and Animal Science (IAAS) Horticulture farm (225 m asl) and at the Agriculture Research Station, Dailekh (1400 m asl) of Nepal Agriculture Research Council (NARC) in the first week of November 2000. All accessions were characterized for leaf erectness, leaf color, leaf wax, leaf cross section, bulb regularity, bulb skin color, bulb outer scales number, days to emergence, bulbing period, number of green leaves at 135 days after planting, days to maturity, plant height, bulb weight, bulb diameter, number of cloves per bulb, clove diameter and bulb yield. Data were analyzed by using principal component and cluster analysis procedures to reveal three major clusters. Four principal components were identified explaining more than 86% of total variation. Major characters included in the principal components were bulb weight, diameter, yield, number of cloves per bulb, maturity, plant height, number of green leaves at 135 days after planting, and bulbing period. The level of variation found in the collection showed the great potentiality of improving agronomic characters in garlic.     

Screening different crested wheatgrass (Agropyron cristatum (L.) Gaertner.) accessions for drought stress tolerance

A pot experiment was conducted in a greenhouse to evaluate the effect of drought stress on growth and turf quality of 24 accessions of crested wheatgrass (Agropyron cristatum (L.) Gaertner.) and ‘Rembrandt’ tall fescue, and to find the most drought-tolerant accession(s) of crested wheatgrass. The grasses were treated in well-watered or exposed to drought stress by withholding water for 20 days. Visual turf quality of drought-stressed plants had no significant differences with well-watered plants until day 8 of drought and 1727 P10 had the highest turf quality at day 20 of drought. Cluster analysis classified the accessions and Rembrandt into five clusters comprised of drought tolerant (I), intermediate (II, IV and V) and susceptible (III) in response to soil drying. Turf quality, green tissue, relative water content and electrolyte leakage of cluster I (1727 M, 208 M, 4056, 2854 and 1727 P1) were 1.8-, 2.0-, 1.6- and 0.6-fold of cluster III (Rembrandt) under drought stress conditions, respectively. Genetic diversity of cluster I could be used for plant breeding programmes and introduction of the drought-tolerant accessions to turfgrass breeders for drought tolerance varietal development programme.     

Study of a germplasm collection of loquat (Eriobotrya japonica Lindl.) by multivariate analysis

Loquat species (Eriobotrya japonica Lindl.) originated in China, later was introduced in Japan. However, introduction in Europe occurred much later, in 18th century, it was introduced as an ornamental tree. Since then, the species was very well adapted to the Mediterranean climate, mainly in South East of Spain, where is located more than 50% of total European crop production. A European Project titled ‘Conservation, evaluation and collection of underutilized fruit species’ supported surveys and collection of plant material from these species in the Mediterranean basin countries. One of these surveys resulted in a germplasm collection of loquat established at IVIA, Valencia, Spain. This collection is being extended with new accessions collected across the world, currently the collection have 123 accessions under study. Germplasm management needs first a characterization of the plant material introduced and second diversity studies into the collection that could point out the variability pattern, to establish groups of accessions with similar traits and the most significant variables. These results allow organizing the information gathered for further uses. In this paper, 62 accessions from the IVIA germplasm collection were studied. Results from 43 variables were gathered and data studied by multivariate analysis. The analysis allowed summarizing the data tables with new variables containing most of the information. These results along with those obtained in the coming years will allow define a nuclear collection (minimum number of accessions that contained all the variability present in the collection).     

Morphological Diversity of Bambara Groundnut [Vigna subterranea (L.) Verdc.] Landraces in Tanzania

A field experiment was conducted in Tanzania for two seasons to assess the genetic diversity of bambara groundnut landraces based on morphological characters. One hundred accessions collected from a wide range of agricultural zones in the country were evaluated in a 10 × 10 triple lattice block design at Maruku station in Bukoba, Tanzania. For the qualitative characters evaluated, considerable morphological variations were observed for growth habit, pod shape and pod colour. Quantitative morphological characters such as peduncle length, number of leaves per plant, terminal leaflet width, terminal leaflet length, petiole length, plant spread, plant length, pod width, seed length, seed width, number of pods per plant, shelling percentage and days to 50% flowering showed significant variation among accessions for the two test seasons. Multivariate analysis for 15 quantitative morphological traits that showed significant variation indicated that the first four PCs with eigenvalues ≥1 accounted for 63.0 and 65.0% of the total variance among the accessions during the two test seasons, respectively. The most important loadings for PC1 and PC2 for the two seasons were terminal leaflet width, terminal leaflet length, petiole length, plant spread, plant height and pod length, pod width, seed length, seed width, numbers of pods per plant. Cluster analysis grouped bambara groundnut accessions into three major groups with respect to their geographic origins. Based on this present study, bambara groundnut landraces from Tanzania displayed a considerable diversity for morphological and agronomic traits useful for germplasm management and utilization into crop improvement.     

Variation of cultivated flax (Linum usitatissimum L. subsp.usitatissimum) and its wild progenitor pale flax (subsp.angustifolium (Huds.) Thell.)

The domestication of cultivated flax (Linum usitatissimum L. subsp.usitatissimum) is briefly discussed. Using data documented as a matter of routine in genebank work, 63 accessions of cultivated flax from the flax germplasm collection of the Gatersleben Genebank are compared with 73 accessions of its wild progenitor pale flax (subsp.angustifolium (Huds.) Thell.), which have been observed in systematic field trials. Range of variation, genetically based variation, heritability and correlation of several characters are considered, especially with respect to the influence of domestication. Cultivated flax shows higher variation in the characters of generative plant parts, while pale flax varies more in the vegetative parts of the plant. The character correlations are similar in both subspecies. Of the 29 characters studied in pale flax the parameters describing tillering, height of plant, weight of seeds, width of petals and width of leaves are especially suitable for distinguishing between different accessions. In spite of the high heritabilities of most of the characters, the influence of the environment is significant in most cases.     

Morphological Variability of Prosopis cineraria (L.) Druce, from the Cholistan Desert, Pakistan

Sixty-two accessions of Prosopis cineraria, collected from different areas of the Cholistan desert and from the vicinity of Islamia University, Bahawalpur during June, 2002 were evaluated for agro-morphological diversity. Data collected revealed considerable variation for pod length, pod thickness, number of seeds per pod, pod weight, 100-seed weight, seed size, number of pinnules, length of pinnae, length of the pinnulae, and breadth of the pinnulae. Accessions GD-1 and GD-2, collected from Gadhen Wala Toba, KWT-1, KWT-3, KWT-4, KWT-6, from Khokhran Wala Toba, TWT-2, TWT-7, TWT-8, from Taraway Wala Toba, CSW-2, CSW-7, CSW-8, from Chah Sulleh Wala, and IUB-5, IUB-9, from Islamia University, Bahawalpur, showed very high variation. Overall, accessions KWT-6 from Khokhran Wala Toba, and TWT-7, from Taraway Wala Toba, (both from Cholistan desert), appeared as best genotypes based on their morphological variation detected in this study.     

Effect of seed storage on germplasm integrity of meadow fescue (Festuca pratensis Huds.)

Qualitative and quantitative changes in populations of meadow fescue (Festuca pratensis Huds.) after seed storage under different conditions were estimated. Phenotypic characters of plants grown from seeds stored for 54 months under two different storage conditions were compared. The germination of most of the seed accessions stored under favourable conditions remained at the initial level while storage under unfavourable conditions resulted in a decrease of the initial germination percentage as well as in an increase in the number of plants showing chlorophyll aberrations. There is great variability among the accessions resulting from storage under unfavourable conditions. In case of a few accessions a decrease in germination below 35% resulted in chlorophyll aberrations, faster flowering, shorter inflorescence and reduced viability of pollen grains.     

Morphological and phenological variation in the wild relatives of lentil

Wild lentils are a potentially important source of genetic variation for the improvement of the cultivated lentil. A lack of evaluation data for characters of economic importance is one constraint to their use in breeding programmes. Here, variation in selected phenological and agro-morphological characters in 310 accessions of wild lentils is reported. This includes 153 accessions of Lens culinaris subsp. orientalis, 33 accessions of L. odemensis, 32 accessions of L. nigricans, 90 accessions of L. ervoides and 2 accessions of L. lamottei. Certain L. culinaris subsp. orientalis accessions had substantially more leaves per plant, peduncles per plant, pods per plant and seeds per plant, and greater leaf area than two cultivated lentil checks. The total biomass obtained from the best L. culinaris subsp. orientalis accessions was comparable with the checks. The harvest index of one check was comparable with that of the two best L. culinaris subsp. orientalis accessions. Of the wild taxa, the L. lamottei had the highest average 100-seed weight. Broad-sense heritabilities were calculated and found to be high for days to average flowering and days to average podding. Significant correlations exist between quantitative characters and latitude of origin. Phenological adaptation, through sensitivity to photoperiod, temperature or both, appear to be a major evolutionary force in wild lentils. Variation is mapped according to geographical origin of accessions in order to identify geographical patterns or clines of variation. Accessions of L. culinaris subsp. orientalis from Uzbekistan, Turkmenistan and Tajikistan had among the largest biomass, the most peduncles per plant and many pods and seeds per plant. One-hundred seed weight, however, did not decline as expected with increased seed number.     

Applications of mineral nitrogen increase the yield and content of crude protein in narrow-leaf lupin seeds

Abstract

In a plant pot experiment with non-inoculated seed stock of narrow-leaf lupin (Lupinus angustifolius, L.) of the variety ‘Prima’ we explored the effects of nitrogen compounds applied in the form of NH₄NO₃ on different dates (before sowing, after emergence and during flowering) and at various levels (0–0.5–2–3 g N per pot) on changes in the number of pods per plant, the 1000-seed weight, seed yields and the content of crude protein in seeds. The experiment included four treatments; the first was a control treatment not fertilized with nitrogen. In the other treatments we applied nitrogen either as a single application before sowing or in three split applications. In all the nitrogen-fertilized variants the number of pods per plant, total seed yields per plant and the concentration of crude protein all increased compared to the unfertilized control variant. The highest levels of nitrogen (3 g N per pot) reduced the 1000-seed weight compared to the unfertilized control variant. The total application of 2 g N per pot split into application before sowing (0.5 g N), after emergence (0.5 g N) and during flowering (1 g N) resulted in a highly significant increase in the number of pods per plant (+78%), the 1000-seed weight (+20.1%) and therefore higher seed yields per plant (+139.8%) compared to the control treatment not fertilized with nitrogen. Increasing levels of nitrogen linearly increased the content of crude protein in seeds during harvest from 24.2% to 40.6%, thus increasing the nutritional quality of the seeds.