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Black pepper is also known as black gold, since this has been traded like gold during the dawn of colonialization. The produce fetches higher price in the market based on its colour, lustre as well as bulk density. Sun-drying is the common method of drying, and due to direct exposure to sunlight, characteristic shiny black colour is deteriorated. Blanching is one of the techniques to retain the colour of dried produce. But this process is time-consuming and requires extra labour and large amount of firewood. In order to find an alternative easier method to retain black colour of berries without affecting the quality parameters, an experiment was conducted with 7 treatments, viz.direct sun-drying, hot water blanching for 1 min, hot water blanching for 2 min, covering with 100- and 300-gauge polythene sheets for 3 and 5 h. Among the different treatments, covering the berries with 100-gauge polythene sheet for 3 or 5 h and subsequent drying under direct sunlight not only retained black colour of dried produce with higher dry recovery (39.31 and 39.39%, respectively) but also did not alter the quality parameters, viz.essential oil (EO) content (2.64 and 2.56%, respectively) and oleoresin content (6.75 and 6.45%, respectively) as compared to conventional sun-drying where the dry recovery percentage was 37.98% with 2.69% of essential oil and 6.96% of oleoresin content.

Foot rot caused by Phytophthora capsici/P. tropicalis, is the most deleterious of all diseases affecting black pepper. Conventional pathogen inoculation and response to biochemical parameters such as lignin and peroxidase activity were targeted for locating source of resistance in black pepper. The direct response of infection as phenotypic symptoms and defense response imparted by lignin and peroxidase activity was studied in eight black pepper varieties, namely 04-P24, IISR Shakthi, Sreekara, Panniyur-1, Malabar Excel, Thevam, Panchami, Pournami and four germplasm accessions (7731, 7583, 8041, 8062) that showed differential response to Phytophthorainfection. Among the varieties tested, 04-P24 showed no symptoms of infection and found as resistant. The response of lignin and peroxidase activity upon infection showed 04-P24 as having highest peroxidase activity with higher lignin content. Based on consecutive results, it is inferred that increased levels of lignin and peroxidase contributed to development of Phytophthoraresistance in black pepper. The study suggests that peroxidase activity can be used as a biochemical marker for screening black pepper plants for Phytophthoraresistance.

ABSTRACTThe essential oil of 28 ginger genotypes was subjected to gas chromatography–mass spectrometry to understand the potential of these genotypes to produce high essential oil with added value. The essential oil and its composition varied among genotypes. The highest essential oil and oleoresin (6.00 and 12.18 %) was recorded in ‘Red ginger’ (Z ingiberofficinalevar. rubrum). Among the ginger (Z. officinale) genotypes, high oil and oleoresin (3.00 and 8.55 %) were recorded in ‘Arunachal local’. The genotypes ‘Acc. 578ʹ, ‘Nadia’ and ‘Aswathi’ recorded less fiber and ‘Red ginger’, ‘Acc. 219ʹ, ‘Arunachal local’ and ‘Acc. 833ʹ recorded high fibre. The Zingiberene was the major component in the essential oil and highest was recorded in ‘Maran’. Principal component analysis revealed essential oil, oleoresin, camphene, trans-nerolidol, α farnesene and neral contributed to genetic diversity. The results contribute to the selection of ginger genotypes for high essential oil and different end use.