Survey of white root rot caused by Dematophora necatrix in apple orchards across six districts of Himachal Pradesh (Shimla, Kullu, Chamba, Sirmour, Mandi, and Solan) was conducted. Data were collected from various locations, documenting the prevalence, disease symptoms, and management practices. Data indicated that disease incidence was in the range of 0.8% to 40%, with the highest occurrence in Rohru (Shimla) and Burwa (Kullu). Wilting, small sized fruits and decayed roots were the commonly observed symptoms on the affected trees. The survey results revealed that orchardists primarily relied on fungicides such as carbendazim, often without following prevenlance of disease, proper application techniques or understanding of disease management. The presence of disease complexes, including co-infections with Phytophthora and Fusarium species, was noted. Findings underscore the urgent need for effective management strategies and better educational outreach for local farmers to mitigate the impacts of white root rot on apple production. The findings of the survey highlights the prevalence of disease in Himachal Pradesh and the kind of symptoms produced.
Losses in wheat yield due to the attack of stripe rust disease caused by Puccinia striiformis f. sp. tritici were assessed under natural field conditions. An experiment was conducted on wheat cultivars having different degree of resistance against stripe rust at three locations continuously for three years in disease prone areas of district Rupnagar, Punjab which is situated in sub-mountainous region of northern India. The infection of stripe rust on cultivar HD 2967 was higher with 80S final rust severity and Area Under Disease Progress Curve (AUDPC) values of 1919 in unprotected plots which caused 72.31% yield reduction. The loss in yield due to stripe rust varied with the resistance level of the cultivar. The correlation coefficient (r) was estimated between wheat yield and disease parameters, revealing a negative correlation. Similarly, net income and the benefit-cost ratio were negatively correlated with disease parameters Final Rust Severity (FRS) and AUDPC, indicating that an increase in disease severity led to greater yield losses and reduced profitability. The relationships between disease parameters and yield components are key factors in guiding the implementation of disease management strategies and assessing their impact on crop productivity and economic returns.
Phytoplasma diseases are common obstacle against vegetable production. Eggplant is one of the major solanaceous vegetable crop which is acutely affected by phytoplasma infection. Little leaf, phyllody and giant calyx are some of the prominent symptoms of phytoplasma infection in eggplant. In present investigation, association of phytoplasma was confirmed with these symptoms by using phytoplasma (16S rRNA gene) specific universal primers (P1/P7). The flower, leaf and calyx tissues of phytoplasma infected plants showing phyllody, little leaf and giant calyx symptoms respectively as well as of healthy plants were fixed in Formalin- Acetic acid- Alcohol (FAA) solution and proceeded for light microscopy. The flower petal, leaf lamella and giant calyx were observed for perceiving microscopic histological changes. The flower and leaf tissues of healthy plants were used as control. In results, it was divulged that phytoplasma infection in eggplant causes many histological wreckings viz., distortion and anarchy of different constitutive cells of dermal, ground and vascular tissues of different plant organs.
Cherry tomatoes are deemed valuable in the market for exotic vegetables and able to fetch a high price in the organic vegetable market. They are becoming increasingly popular for both culinary use and as fresh ingredients in salads. The main obstacles in cherry tomato production in Punjab include late blight in the early spring season and ToLCVD during the rainy season. The aim of the present study was to evaluate the germplasm through artificial inoculation against ToLCVD and late blight disease. Three genotypes against ToLCVD namely PCT-10, PCT-42 and PCT-47 showed symptomless reaction (doesn’t confirm total immunity, but just the absence of symptoms). PCT-60 was highly resistant to late blight, while PCT-9, PCT-11, PCT-13, PCT-29, PCT-42, PCT-46, PCT-51 and Punjab Red Cherry demonstrated resistant reaction against late blight. One genotype PCT-42 exhibited no symptoms of leaf curl and displayed resistance against late blight. These genotypes can be employed in subsequent breeding endeavours to cultivate plants with enhanced resistance to biotic stress.
The present study delved into the integrated management of Alternaria blight, a major threat to marigold (Tagetes erecta L.) cultivation, caused by Alternaria tagetica. The experiment was conducted in the department of floriculture and landscaping, Punjab Agricultural University, Ludhiana during 2022 and 2023. Efficacy of six fungicides and botanicals was evaluated against Alternaria tagetica under in vitro conditions. Tebuconazole+trifloxystrobin gave maximum inhibition (100, 92.22, 89.63, 86.67, 85.56 %) followed by Azoxystrobin (100, 91.11, 82.22,76.67,70.37%),Tebuconazole (100, 90.00, 79.63, 75.19,64.44%),Difenoconazole (100,86.67,78.00,72.96,59.96%) and Metiram (90.74,82.96, 77.80,59.63, 54.45%) at 400,200, 100, 50 and 25 ppm concentration, respectively. Minimum inhibition (69.63, 64.81, 52.22, 37.41,29.26%) was observed in Chlorothalonil at all the five concentrations. Among the six botanicals tested Allium sativum, Azadirachta indica and Moringa oleifera showed strong antifungal activity with 78.89, 69.26 and 67.04 percent respectively at 2000 ppm. Minimum fungal inhibition was observed by Terminalia arjuna (35.14%). Overall, the findings showed the potential of integrated disease management strategies involving fungicides and botanicals to mitigate the Alternaria leaf spot in marigold.
