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Multivariate analysis was conducted to explore the moist temperate forests of the Shangla district, Khyber Pakhtunkhwa. The prime objective was to quantitatively describe and differentiate the vegetation groups and the factors that determine the boundaries and composition of plant communities in the Shangla district. This was achieved by sampling all common species in a complex vegetation mosaic coinciding with local gradients in topography and soil distribution. Ward’s clustering dendrogram demonstrated four significant vegetation clusters with respect to environmental effects. These four major groups of the tree vegetation were superimposed on the ordination plane: 1. Pinus wallichiana, the dominant group associated with Abies pindrow; 2. Abies pindrow and the Picea smithiana group; 3. Dominant Cedrus deodara associated with the Pinus wallichiana, Abies pindrow, Picea smithiana, and Quercus baloot group; 4. Pinus roxberghii pure group. The key controlling factors for each group were the environmental characteristics (i.e., edaphic factors, topographic factors, soil physical properties, and soil nutrients). The results revealed elevation (p p < 0.05) relationship with vegetation. The other environmental factor did not show a significant relationship with vegetation. Ward’s cluster dendrogram of understory species also demonstrated four groups. Group 1 comprises two subgroups, a and b, with the highest number of species, i.e., Digeteria sanguinalis, Fragaria nubicola, Verbascum Thapsus, Pinus wallichiana seedlings, and Polygonatum multiflorium, respectively. The second large group contains twenty-five species out of eight stands, and the dominant species was Tagetis minuta. Eighteen species out of six stands were found in group 3, which was considered the smallest group. Group 4 consisted of seven stands containing twenty-four species of ground flora, with Anaphalis scopulosa followed by Adiantum venustum as the dominant species. The environmental characteristics of the understory vegetation showed a resemblance with the tree communities. With the exception of elevation, the other factors did not show a significant correlation.

Aconitum violaceum Jacq. ex Stapf is a threatened medicinal plant with restricted global distribution. The highest frequency of seed germination was recorded on Murashige and Skoog’s (MS) basal medium, supplemented with 0.5 mg L−1 kinetin with a germination rate of 77.32% and mean germination time of 27 days. Among the various plant growth regulators examined, 0.1 mg L−1 kinetin (Kn) + 0.5 mg L−1 indole-3-acetic acid (IAA) proved to be effective for maximum embryogenic callus production (51.0%) within 31 days of inoculation. The conversion rate of somatic embryos into complete plantlets was highest in the MS medium augmented with 0.1 mg L−1 Kn + 0.5 mg L−1 IAA (68.00%), with an average root initiation time of 25 days. The rooted plantlets were subsequently hardened into jiffy pots with a combination of loamy soil, coco-peat, and vermicompost (1:1:1 v/v), and then transplanted into a greenhouse with a 60% survival rate. To our knowledge, this is the first study on direct in vitro propagation and embryogenic callus induction from seeds. The established regeneration protocol could be employed to propagate A. violaceum on a large scale in a short time. This would contribute significantly to its rapid propagation and germplasm conservation, and establish a framework for the domestication of this highly valued threatened medicinal plant.

Powdery mildew is an omnipresent disease that reduces the yield and quality of pea crops (Pisum sativum L.). To examine the powdery mildew pathogen’s morphological, molecular, and genetic diversity, we collected samples of powdery mildew-affected pea crops from ten distinct locations in the Nilgiris district of Tamil Nadu, India. The pathogen Erysiphe pisi was identified morphologically based on anamorphic characters. Molecular identification of E. pisi isolates was befitted by targeting the internal transcribed spacer (ITS) region of rDNA and specific primers of powdery mildew fungi. The genetic variation between ten different E. pisi isolates collected from topographically distinct mountainous areas was studied using random amplified polymorphic (RAPD). Based on its morphological characteristics, the powdery mildew fungus presented high similarities to E. pisi. Molecular characterization of the ITS rDNA of E. pisi produced 650 bp nucleotides, PMITS (powdery mildew-internal transcribed region) primers produced 700 bp nucleotides, and an Erysiphe specific ITS primer pair amplified and synthesized 560 bp nucleotides. According to the findings, the collected E. pisi strains exhibited a low level of genetic diversity and only a slight differential in virulence on the host. In the study, E. pisi isolates from Anumapuram, Emerald Valley, Indira Nagar, and Thuneri showed a greater disease incidence in the natural field conditions and shared the same genetic lineage with other isolates in UPGMA hierarchical cluster analysis based on RAPD markers. There was no evidence of a link between the occurrence of the disease and these grouped populations.

Wild relatives of okra represent a good source of variation for breeding programs, particularly for traits related to biotic and abiotic stresses and fruit quality. However, wild species remain largely unexploited for okra breeding. The cultivated okra accession Abelmoschus esculentus cv. ‘Arka Anamika’ was crossed with three wild accessions: Abelmoschus manihot, Abelmoschus ficulens and Abelmoschus moschatus. The crossability was estimated based on fruit set, seed set and germination rate. The results of cross compatibility studies revealed that the crosses are compatible only when cultivated A. esculentus is used as a female, and reciprocal crosses were not successful in any of the three wild species. Higher fruit set (87.2%) and seed germination (92%) were obtained from the crosses ‘Arka Anamika’ × Abelmoschus manihot. The interspecific F1s exhibited normal growth, flowering and fruit formation, but the hybrids were completely sterile on selfing due to abnormal meiosis. Characterization of the parents and interspecific hybrids revealed that the interspecific hybrids were generally more vigorous than the parents and displayed greater alliance towards their wild parent. The sterile F1s were further treated with 0.1% colchicine to restore fertility. The three interspecific crosses showed considerable differences in mean performance and heterosis over mid parent and better parent. The cross ‘A. Anamika’ × A. manihot displayed positive heterosis over mid parent and better parent for the yield traits, viz., fruit yield per plant, number of fruits per plant, number of primary branches per plant and plant height. The information obtained in the study on crossability relationship, phenotypic characterization and heterosis in interspecific hybrids will assist breeders in the development of prebreeding material.