The fruit fly Bactrocera caryeae (Kapoor) (Diptera: Tephritidae) is an economically important pest of several tropical and subtropical fruit crops. Understanding its host range and natural enemy complex is critical for effective pest management and quarantine risk assessment. The present study investigated the host plant range of B. caryeae and documented its parasitoid assemblage through systematic field surveys and fruit rearing studies. A total of 23 fruit species belonging to 12 plant families were recorded as hosts, with Avocado (Persea americana), Karonda (Carissa carandus), Malayan apple (Syzygium malaccense) and Amtekayi (Spondias dulcis) identified as major hosts. Ahymenopteran parasitoid Diachasmimorpha longicaudata was recovered from B. caryeae pupae, as dominant species with 100 % parasitisation. The findings highlight the ecological adaptability of B. caryeae and emphasize the role of parasitoids in regulating its populations, providing valuable insights for integrated pest management and biological control programs.
Fusarium wilt of banana, incited by a soil borne fungus Fusarium oxysporum f.sp. cubense (Foc) considered as a global enigma to the banana cultivation has garnered significant importance in recent times. The symptomatology of Fusarium wilt in banana illustrates a sophisticated and persistent pathology, one that operates below the surface long before visible signs appear. Understanding the full range of symptom expressions, both external and internal symptoms are essential for early detection. The genetic plasticity, and long-term soil persistence of Foc makes the management approaches a daunting task and necessitate an integrated approach to surveillance, quarantine enforcement, molecular diagnostics, and resistant cultivar development and most importantly its management through ecologically benign approaches. Use of rhizospheric and endophytic bioagents could be introduced as a new normal strategy in management frontiers. This review aims to provide a comprehensive overview of the current knowledge on Foc, covering its biology, pathogenic variability, survival strategies, and the evolving landscape of biological control options. Accordingly, we identify critical knowledge gaps, particularly in the Indian context, and outline strategic directions for future research to inform bio-based green management approaches against this resurgent phytopathogen.
A study on the biology of the ginger shoot borer, Conogethes punctiferalis Guenee, conducted during 2024 at the College of Agriculture, Shivamogga, Karnataka, showed that the incubation, larval, pre-pupal and pupal periods were 3.72 ± 0.25, 21.25 ± 1.76, 2.90 ± 0.20 and 7.75 ± 0.29 days, respectively. On ginger, the mean pre-oviposition, oviposition and post-oviposition periods lasted 3.00 ± 0.50, 2.40 ± 0.22 and 2.60 ± 0.22 days, respectively. A female laid an average of 45.00 ± 8.12 eggs. Adult longevity of male and female moths was 7.20 ± 0.27 and 7.90 ± 0.65 days, respectively. The total life cycle on ginger was 42.50 ± 3.53 days for males and 43.50 ± 4.24 days for females. In the bio-efficacy trial against the ginger shoot borer, spinetoram 11.7 % SC @100 ml/acre was the most effective insecticide, reducing damage by 60.61 per cent over the untreated control and recording the lowest mean damage across both sprays. Lambda-cyhalothrin 5 % EC @ 80 ml/acre offered better sustained control, whereas cartap hydrochloride 4 % G @ 10,000 g/acre, chlorantraniliprole 0.4 % G @ 4,000 g/acre, imidacloprid 70 % WG @ 400 g/acre and azadirachtin 1 % EC @ 400 ml/acre were moderately effective in managing the ginger shoot borer.
Twig blight of chilli is a complex disease associated with multiple pathogens and has emerged as a major constraint to chilli cultivation, causing recurrent outbreaks, substantial yield losses and posing a serious threat to crop productivity. In the present investigation, a random roving survey was undertaken in major chilli-growing regions of Karnataka to assess the incidence and severity of the twig blight disease. Symptomatic plant samples were collected and subjected to isolation on potato dextrose agar. The obtained cultures were characterized based on their cultural and morphological traits. Colonies were white, submerged and exhibited rapid growth, with secondary mycelium developing within two days and the reverse side of the plate showing a pale-yellow pigmentation. Sporangiospores were brown, ellipsoidal and devoid of striations or papillae. For molecular confirmation, genomic DNA was amplified using universal primers (ITS-1 and ITS-4), yielding a ~600 bp fragment of the Internal Transcribed Spacer (ITS) region of rDNA. Sequencing and BLAST analysis against the NCBI database sequences confirmed the identity of the pathogen as Choanephora cucurbitarum.
An experiment on screening tomato genotypes against major sucking pests was conducted during the Rabi season 2023-24. The study identified NDT-2021-1 and NDT-2022-2, along with NDT-2021-3 and NDT-2022-4, as promising genotypes against whitefly, Bemisia tabaci (Gennadius), jassids, Amrasca biguttula biguttula (Ishida), and aphid, Aphis gossypii Glov. Anatomical traits such as trichomes on the leaf and calyx and pericarp thickness, together with the biochemical compound phenol, played an important role in imparting resistance in these tomato genotypes. In contrast, protein, lycopene, carbohydrate, chlorophyll, carotenoid, and peroxidase enzyme activity showed positive correlation with pest incidence. The study therefore indicates that both biophysical parameters and biochemical characteristics contribute significantly to the mechanisms of resistance.
