The present study evaluated the effect of different stocking densities on the growth performance, cannibalism and survival of Asian seabass (Lates calcarifer) fry reared in an indoor recirculating aquaculture system (RAS). Fry (25 days post-hatch) were stocked at three densities: 100T1, 200T2, and 300(T3) individuals per m3 and reared for 50 days under controlled conditions. Growth parameters, water quality, cannibalism rate and survival were monitored throughout the study. Water quality parameters remained within acceptable limits across treatments, although slight variations were observed with increasing density. Fish reared at the lowest density (T1) exhibited significantly higher growth performance, with maximum length gain (8.40±0.95cm), weight gain (10.2 ± 0.16g) and better feed conversion efficiency. In contrast, higher stocking densities (T2 and T3) resulted in reduced growth and feed efficiency. Cannibalism rate increased significantly with density, reaching the highest value in T3(13.55 ± 2.84%), while survival rate decreased from 96.54 per cent in T1 to 86.45 per cent in T3. The results indicated that lower stocking density improves growth performance, reduces cannibalism and enhances survival in Asian seabass fry under RAS conditions. Optimizing stocking density is therefore critical for sustainable and efficient nursery rearing of seabass.
The present review focuses on the distribution, regeneration status and nutritive potential of Quercus glauca Thunberg in the Indian Himalayan region. The species is widely distributed in the northwestern Himalaya, particularly in Himachal Pradesh and Uttarakhand, where it grows in moist and shady habitats and forms an important component of evergreen broadleaf forests. It is closely associated with rural livelihoods and serves as a valuable fodder resource for livestock. The leaves of Q glauca possess high nutritive value with considerable crude protein, mineral content and moderate fibre composition, making it suitable for sustaining livestock productivity in hill agroecosystems. Despite its ecological and economic importance, the species is facing serious challenges in natural regeneration due to anthropogenic disturbances, overgrazing, limited seed viability, poor dispersal and changing climatic conditions. Seed germination in Quercus species is influenced by several factors including seed size, altitude, time of collection and pre-sowing treatments. Physical treatments such as scarification and water soaking along with proper nursery management have been found effective in improving germination and seedling establishment. The review highlights that regeneration of Q glauca is site-specific and favoured under moderate disturbance and adequate canopy gaps. However, overall regeneration remains inadequate across its natural distribution range. The study emphasizes the need for integrated management strategies focusing on habitat conservation, improvement in regeneration techniques and sustainable utilization of the species.
The present study was conducted to evaluate the effect of grafting time and growing conditions on growth dynamics of ber (Ziziphus mauritiana L) under semi-arid conditions of Hisar, Haryana. The experiment involved wedge grafting of two cultivars, Gola and Umran, at eight different time intervals from the third week of January to the second week of March under open field and polyhouse conditions. The trial was laid out in a randomized block design with three replications. The results revealed that grafting time significantly influenced all growth parameters studied, whereas, growing conditions and cultivars showed variable responses. Grafting during the fourth week of February consistently recorded the highest values for leaf area (1,842.78cm2), chlorophyll ‘a’ (1.004mg/gFW), chlorophyll ‘b’ (0.472mg/gFW), fresh root weight (27.41 g) and dry root weight (15.21 g). In contrast, grafting during the third week of January resulted in the lowest values for most traits. Open field conditions generally performed better than polyhouse conditions in terms of leaf area and chlorophyll content. Among cultivars, Umran exhibited comparatively better vegetative growth, though differences were mostly non-significant. The study highlights that appropriate grafting time plays a crucial role in enhancing physiological efficiency and growth performance in ber. Late February emerged as the most suitable period for grafting under the prevailing agroclimatic conditions.
Forestry plantations in the northwest Himalayas are increasingly threatened by insect pests such as Agrotis ipsilon and Plecoptera reflexa, which cause severe defoliation and economic losses. The present study evaluated the pesticidal potential of leaf extracts of the native plant Boenninghausenia albiflora (Hook) against these two major forest insect pests under laboratory conditions. Leaf extracts were prepared using methanol, acetone and ethyl acetate and their insecticidal efficacy was assessed using the leaf-dip bioassay method. Among the tested solvents, the methanolic extract showed the highest extraction yield (18.58%) and insecticidal activity, causing 60.00 per cent mortality in P reflexa and 56.66 per cent mortality in A ipsilon at 1 per cent concentration after 72 h . Further bioassay of the methanolic extract at graded concentrations (0.25-1%) demonstrated a dose-dependent increase in larval mortality. The LC50(%) values ranged from 0.81 to 0.89 per cent for P reflexa and 0.86 to 0.96 per cent for A ipsilon. GC-MS analysis revealed that the extract was rich in bioactive terpenoids, with a-pinene (16.56%),(+)-sylvestrene (16.27%), ß-pinene (14.82%) and carvone (6.51%) as the major constituents. These compounds are known to possess insecticidal, repellent and neurotoxic effects against insect pests. The findings demonstrate that B albiflora leaf extract possesses significant insecticidal activity and may serve as a promising eco-friendly botanical alternative for the management of forest insect pests in the northwest Himalayan region.
The present investigations were carried out to evaluate the trait association and selection strategies of F3 and F4 segregating generations on growth, flowering and yield-related traits in bottle gourd {Lagenaria siceraria (Mol) Standl\ under the agro-climatic conditions of southwestern Haryana. The study was conducted during the rainy season of 2022-23 at CCS Haryana Agricultural University, Hisar, Haryana using progenies derived from the F2 population of hybrid 19BOGHYB-2. Five progenies were advanced and evaluated in both F3 and F4 generations in a randomized block design with three replications. Analysis of variance revealed highly significant differences among progenies for all sixteen traits studied, indicating the presence of substantial genetic variability. In both generations, progeny 1 consistently exhibited superior performance for important traits such as number of primary branches per plant (11.73 and 11.47), average fruit weight (793.33 and 813.33 g), number of fruits per vine (8.13 and 8.40) and fruit yield per plot (64.57 and 68.30 kg). Early flowering and earliness in fruit harvest were also observed in this progeny, making it desirable for selection. The results indicated that selection in early segregating generations is effective for improving yield and its contributing traits. Progenies 1 and 2 emerged as promising lines and may be further utilized in breeding programmes aimed at developing high-yielding and early-maturing varieties of bottle gourd.
