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Avocado (Persea americana Mill.) is emerging as one of the high-valued fruit crops in India. Recently, demand for avocados is increasing due to the high nutritional value of the fruits. Currently, avocados are not grown on large commercial scale and there is a need of good high yielding varieties for commercial cultivation. Hence knowledge on genetic diversity of avocado is essential for selection of superior genotypes. Currently, the information on genetic diversity of Indian avocados is limited. Therefore, an intensive survey was carried out in major avocado growing areas of India to collect 83 diverse accessions. The collected accessions were characterized for 27 characters using IPGRI, avocado descriptors. Among the characters studied, 2 characters were dimorphic and remaining 25 were polymorphic. The maximum accessions showed the presence of rough trunk surface (48.19%), oval leaf shape (44.58%), acute leaf base (86.75%) and leaf apex (72.29%). The dominance of light green fruit colour (38.55%) with smooth peel surface (54.22%) was noticed. The wide variability for pulp and seed characters was also documented. The principal component analysis and cluster analysis showed the existence of wider variability among the collected accessions. The existence of huge diversity helps to conserve trait specific accessions and varietal improvement through selections and hybridizations.

This endeavor includes thirty grapes' genotypes grown in northern zones of Punjab, Pakistan to determine similarities and dissimilarities in forty-four morphological traits according to the descriptor "International Plant Genetic Resources Institute (IPGRI)". The relation between the genotypes was determined by principal component analysis (PCA), and similarity was worked out by using cluster analysis. The dendrogram divided the genotypes into two main groups with classes and subclasses. The variation present within the class was up to 81.72% while the difference between classes was 18.28%. The morphological quantitative traits such as bunch length, bunch width, bunch weight, peduncle length, the weight of 10 berries, number of berry in a bunch, berry length, and berry width were in the following range 27.50-11 cm, 13.75-5 cm, 583.56-77.70 g, 6.50-1.55 cm, 53.70-9.70 g, 354-28, 27.37-11.40 mm and 18.06-10.41 mm respectively, which indicated a wide level of diversity in the selected genotypes. Based on phenological attributes, "Regina", "Perlet", and "Early White" were found early maturing genotypes to prevent berry rotting due to monsoon rains at the final stage of ripening. The data generated in this study would be helpful to preserve the existing germplasm and be available for designing future breeding programs. [ABSTRACT FROM AUTHOR]

Fall armyworm (Spodoptera frugiperda (J. E. Smith)) (FAW) is a petrifying invasive pest of maize (Zea mays L.) in Africa. Ten tropical maize accessions from the International Plant Genetic Resources Institute (IPGRI) collections and a check (Ikom White variety) were studied, under rainfed conditions, in a multi-environment trial (MET) to assess their responses to natural infestation of FAW. The study was conducted in the 2018 first and second maize cropping seasons in Cross River State, Nigeria using a genotype x season interaction (GSI) model. The combined analyses of variance showed non-significant difference (p > 0.05) for genotypes and significant (p = 0.05) genotype x season interactions for seedling emergence, plant height, number of leaves, leaf area and FAW infestation. The most FAW-damaged maize accession in this study was TZm-304 while TZm-1427 was the least FAW-damaged maize accession. Overall, FAW infestation was significantly (p = 0.01) higher in the second maize cropping season (Akpabuyo) than in first maize cropping season (Calabar). This subsequently led to corresponding decreases in early vegetative growth in the second maize cropping season. The IPGRI African maize accessions evaluated in this study were all susceptible to FAW damage at their early vegetative growth stages. However, the infestation dynamics of FAW on maize in Africa is presently being understudied. Thus, there is a dire need for the adoption of a genotype x location x year (GLY) model in subsequent MET studies on FAW across all maize-growing States in Nigeria and selection for maize genotypes in breeding for resistance to FAW should consider early vegetative growth stage and initial establishments in the field as useful aids to selection. [ABSTRACT FROM AUTHOR]

Pumpkin (Cucurbita spp.) is an important indigenous crop in Africa with high nutritional, medicinal and economic value. In Kenya, pumpkins still remain underutilised and neglected; as a result may face extinction. In this study, morphological diversity of eighty pumpkin samples from eight counties in western Kenya were evaluated based on qualitative and quantitative fruit characters, using International Plant Genetic Resources Institute (IPGRI) minimum descriptor for Cucurbitacea as a scoring guide. Principal component analysis (PCA) and cluster analysis of the morphological data, was conducted using XLSTAT 2017 software. Results showed that the first four principal components (PCs) were the most significant, accounting for a total variation of 73.85%. A scatterplot of the first two PCs accounted for 50.19% of the total variation. Majority of the samples were densely scattered. Cluster analysis and the similarity dendrogram grouped the samples into five clusters. The most effective characters for discriminating pumpkin fruits were fruit diameter, fruit width, fruit length, and length to diameter ratio. These may be described as fruit yield characters with desirable traits for productivity, therefore, presenting a good opportunity for breeders to improve pumpkins and for screening and selecting germplasms. [ABSTRACT FROM AUTHOR]

Phenotypic variation in plants can be evaluated by morphological characterization using visual attributes. Fruits have been the major descriptors for identification of different varieties of fruit crops. However, even in their absence, farmers, breeders and interested stakeholders require to distinguish between different mango varieties. This study aimed at determining diversity in mango germplasm from the Upper Athi River (UAR) and providing useful alternative descriptors for the identification of different mango varieties in the absence of fruits. A total of 20 International Plant Genetic Resources Institute (IPGRI) descriptors for mango were selected for use in the visual assessment of 98 mango accessions from 15 sites of the UAR region of eastern Kenya. Purposive sampling was used to identify farmers growing diverse varieties of mangoes. Evaluation of the descriptors was performed on-site and the data collected were then subjected to multivariate analysis including Principal Component Analysis (PCA) and Cluster analysis, one-way analysis of variance (ANOVA) and Chi square tests. Results classified the accessions into two major groups corresponding to indigenous and exotic varieties. The PCA showed the first six principal components accounting for 75.12% of the total variance. A strong and highly significant correlation was observed between the color of fully grown leaves, leaf blade width, leaf blade length and petiole length and also between the leaf attitude, color of young leaf, stem circumference, tree height, leaf margin, growth habit and fragrance. Useful descriptors for morphological evaluation were 14 out of the selected 20; however, ANOVA and Chi square test revealed that diversity in the accessions was majorly as a result of variations in color of young leaves, leaf attitude, leaf texture, growth habit, leaf blade length, leaf blade width and petiole length traits. These results reveal that mango germplasm in the UAR has significant diversity and that other morphological traits apart from fruits can be useful in morphological characterization of mango. [ABSTRACT FROM AUTHOR]

The greatest diversity of tomato is found in wild tomato species that show variability in fruit quality characteristics such as fl avor, aroma, color and texture. Twenty-seven introductions of cherry tomato (Solanum lycopersicum Linnaeus) from UNAPAL's germplasm collection were characterized at Montelindo farm owned by Universidad de Caldas, located in the village municipality of Santágueda, Palestina, Caldas, with an 22.8 °C average temperature, 1.010 m height, 2.200 mm annual precipitation, 76% relative humidity, and volcanic ash and sandy loam soils. Morphological characterization of the introductions was carried out based on tomato descriptors from International Bioversity (formerly IPGRI). An experimental design of randomized complete blocks with 27 treatments, three blocks and seven plants/block as an experimental unit, sown at 1.5 m x 0.5 m (13,333 plants /ha) was used. Four of the nine qualitative and four of the six quantitative variables evaluated showed significant differences. In exterior color of ripe fruit and hypocotyl color, intermediate intensity at 65,38 and 60,85% of the introductions was present, respectively. Introduction 157, stood out with the highest values in the length and width of fruit with 5,03 and 7,00 cm. This one, along with introduction 1.622, showed the greatest length and width of the primary leaf with 4,19 cm-4,02 cm and 0,69 cm-0,72 cm, respectively. The study shows great phenotypic diversity in the introductions characterized which can be useful for genetic improvement of the cultivated species. [ABSTRACT FROM AUTHOR]

• Spanish pepper landraces still lack exhaustive characterization. • Conventional and digital traits are useful for pepper germplasm characterization. • Digital traits have a higher differentiating ability than conventional descriptors. • Fruits are responsible for most of variability within C. annuum varieties. • Typification of these materials is highly relevant for peppers breeding programs. Spain is a relevant secondary centre of diversity for Capsicum annuum peppers, especially for the bell types known as Pimiento Morrón or Pimiento de Morro. Thus, a myriad of highly regarded landraces adapted to a wide range of conditions can be found throughout the country, as a result of centuries of farmers breeding. Despite that, these materials lack of proper characterization, of paramount importance for farmers, breeders and germplasm management. In this regard, in addition to internationally accepted conventional descriptors, high-throughput digital phenotyping tools like Tomato Analyzer, a software originally developed to process scanned images of cut tomato fruits and to record a range of morphological parameters, may provide an important help towards exhaustive germplasm characterization. With this aim, 32 conventional and 35 Tomato Analyzer digital traits were used herein to characterize a large collection of C. annuum accessions from all Spanish regions, including Protected Designations of Origin and Protected Geographical Indications, with emphasis on Morrón peppers, in order to assess the diversity within Spanish elite germplasm and to test the efficiency of those methods to differentiate varietal types and closely related materials. A considerable amount of variation was found using both conventional and digital traits, even within Morrón pepper groups, reflecting the diversity of Spanish peppers in terms of plant and fruit morphology, essential for future breeding programs. Both conventional descriptors and digital parameters were able to distinguish varietal groups. However, on the whole, digital phenotyping was able to discriminate in a more accurate way. Most digital parameters were able to discriminate varietal groups into higher numbers of categories (≥4) than conventional traits (usually 2–4). In addition, the number of significant pairwise differences among varietal groups was considerably higher for digital parameters than for conventional descriptors, enabling a powerful separation, particularly relevant for closely related groups such as Morrón peppers. Likewise, as revealed by Principal Components Analysis, digital phenotyping allowed a more powerful intra-varietal separation compared to conventional descriptors. Finally, a subset of 4 conventional descriptors and 13 Tomato Analyzer traits were identified as the most discriminant to distinguish among closely related C. annuum accessions, explaining 81.81 % of total variance found by Principal Components Analysis. Fruit traits explained the highest percentage of variance for our collection. [ABSTRACT FROM AUTHOR]