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Tea mosquito bug (TMB) is a serious pest of cocoa whose prevalence is high, mostly during summer and post monsoon season. Three species of tea mosquito bug have been reported on cocoa: Helopeltis antonii Signoret, H. theivora Waterhouse, and H. bradyi Waterhouse. H. theivora is the most prevalent one causing damage to young shoots, cherelles and pods. Rearing of tea mosquito bug on cocoa was found to be a failure in the present study hence Helopeltis theivora Waterhouse was maintained on the alternate host mile-a-minute (Mikania micrantha Kunth) under laboratory condition in insect rearing cages. Using freshly reared tea mosquito bugs twenty cocoa hybrids were screened for resistance and were ranked after 72 hours of screening. All the hybrids having less than three lesions per plant in seedlings and less than 33 lesions on pods were ranked as highly resistant. It was observed that hybrids classified as highly resistant had significantly higher phenol content than those classified as susceptible. The significantly low phenol content in the susceptible hybrids suggests that phenolics have a function in mediating resistance to tea mosquito bug in cocoa. From correlation and regression analysis it is confirmed that phenol content can be used as a potential marker indicating the level of resistance of cocoa hybrids against tea mosquito bug resistance.

Chrysanthemum is a herbaceous perennial flowering crop that holds great potential for commercial cultivation. Fifteen chrysanthemum genotypes were studied at the Department of Floriculture and Landscaping, College of Agriculture, Vellanikkara, Kerala Agricultural University, Thrissur, Kerala during 2022 for variability studies in morphological, flowering and post-harvest parameters. Significant variations were recorded among the genotypes for all the traits. Cluster analysis grouped the 15 chrysanthemum genotypes into 4 clusters based on all the characters. Cluster 2 consists of maximum number of 5 genotypes followed by 4 genotypes each in cluster 3 and cluster 4. Highest intra-cluster distance was recorded for cluster 2 and highest inter-cluster distance was observed between cluster 1 and 4. Results revealed that GCV was greater than the equivalent PCV, indicating that the environment had a negligible influence on phenotypic variation. High heritability coupled with high genetic advance for all the characters, indicating additive gene effect suggests that there is excellent scope for selection and improvement. Flower yield per plant showed a substantial positive correlation with flowers/plant, flower diameter, stalk length, stalk girth and flower weight at both phenotypic and genotypic level which could be focused for yield improvement.

The article offers information on the genotypic and seasonal variations affecting yield attributes of cocoa varieties. It mentions the impact of climate change and weather variability on arecanut and cocoa in humid tropics of India, along with discusses the climatic requirements for the growth and development of cocoa.

Vascular streak dieback is a serious disease of cocoa throughout the world and breeding of resistant varieties is the most reliable management strategy. Molecular markers linked with resistance enable marker-assisted breeding by tracking the resistance genes in each generation. To identify the markers linked with resistance, four accessions each of highly resistant, highly susceptible and partially resistant categories were screened with ISSR and SSR primers. Of the 71 ISSR and 46 SSR primers used, five ISSR primers UBC811, UBC815, UBC826, UBC857 and UBC866 have yielded reproducible markers for resistance. Cloning and sequencing of UBC857 marker showed 94% identity with SSR clone mTcCIR42. Screening of genotypes with mTcCIR42 primers generated distinct markers for resistance. Identified ISSR markers represent at least three different genes. Results were further validated using the resistant and susceptible progenies and are being used in marker-assisted selection for VSD resistance in cocoa. [ABSTRACT FROM AUTHOR]

One hundred and thirty five chilli landraces belonging to Capsicum annuum, C. chinense and C. frutescens species were analyzed for 20 unit characters. Temporal and spatial gene expression patterns of anthocyanin pigmentation and pubescence were analyzed which revealed species specific fixation of alleles and differential response of each species to the external environment. Relative fixation of alleles across species was used to frame taxonomic key based on seed and seedling characters which will be helpful for species alignment in the vegetative stage and will be complementary to the existing key. The relationship between C. chinense and C. frutescens was evident from many phenotypic character states with similar expression patterns in both the species. [ABSTRACT FROM AUTHOR]

Cross incompatibility is a major constraint in cocoa research and understanding similarity or dissimilarity among the varieties before establishing clonal gardens is essential for propagation and further improvement. Morphological analysis with respect to the selected quantitative and qualitative pod characters were taken for the present diversity analysis. Six qualitative and eight quantitative pod and bean characters of each variety were recorded as per the standard descriptors. The genetic associations among the varieties were estimated through Jaccard's similarity coefficients using NTSYSpc version 2.1. Cluster analysis was done on the similarity matrix and dendrogram was constructed using Unweighted Pair-Group Method (UPGMA). Diversity analysis based on qualitative and quantitative traits grouped the ten cocoa varieties into five clusters at 68 per cent similarity level. Homology between qualitative and quantitative clustering pattern was also worked out and significant variation was observed in distribution pattern of varieties under study. The polyclonal garden layout designed based on the present diversity analysis can be made use of for ensuring maximum pod set when cocoa is intercroped with coconut. [ABSTRACT FROM AUTHOR]

Cocoa (Theobroma cacao L.) is the only source of chocolate. Artificial synthesis of chocolate is presently impossible due its complex chemical composition. In India commercial cultivation of cocoa started during 1970 and the country is considered as a potential source for cocoa by many chocolate companies. Cocoa exhibits heterosis in yield and yield contributing characters and development of hybrids have played a key role in uplifting cocoa cultivation in many countries. Kerala Agricultural University (KAU) had a vital role in developing cocoa cultivation in India with superior planting materials and improved agro techniques. Thousands of hybrids evolved as the part of hybridization programmes were field established and evaluated for more than twelve years for their consistent performance. The present study envisaged the evaluation of forty hybrids developed through various breeding programmes. As a result of this study five hybrids were identified as superior with high yield and other desirable pod and bean characters. They also exceeded in performance over the check variety CCRP 8, most popular hybrid among farmers which was released earlier by Cocoa Research Centre of KAU. Hence these hybrids viz. CCRP 11 (SIV 1.26), CCRP 12 (SIV 2.29), CCRP 13 (SIV 4.29), CCRP 14 (SIV 6.18) and CCRP 15 (VSD I 31.8) were released by the Government for commercial cultivation during 2015. [ABSTRACT FROM AUTHOR]

Cocoa is one of the important plantation crops grown in India. The Mondelez International, formerly Cadbury, played a significant role in commercialising cocoa cultivation in India. At present, it is cultivated in Andhra Pradesh, Kerala, Tamil Nadu and Karnataka. The present study aims to find the trend in area, production and productivity of cocoa in Kerala during the period from 1978-79 to 2018-19. It also analyses the price behaviour of cocoa in four major markets of Kerala during the period from 2005-06 to 2021-22. The area, production and productivity of cocoa in Kerala indicated an increasing trend over the years. The increase in production of cocoa in Kerala could be attributed to the growth in productivity rather than area. The prices of cocoa in all the major markets of Kerala showed increasing trend during the period from 2005-06 to 2021-22. The prices in Kerala were found to be the lowest during the months from August to October, while the prices were highest during the months of April and May. The cyclical and irregular variations of cocoa prices in Kerala were found to be insignificant. [ABSTRACT FROM AUTHOR]

Fifteen chrysanthemum genotypes were evaluated in RBD with three replications to select suitable genotypes for cultivation in the plains of Kerala. Significant variations were reported among the genotypes for all the traits. KAU C-7 recorded highest plant spread (47.95 cm), number of primary branches per plant (17.50) and number of leaves per branch (21.50). Earliest flower bud initiation (38.85 days) and 50 % flowering (42.80 days) was recorded in KAU C-1. KAU C-8 took minimum number of days to complete opening of a flower (35.85 days). Greatest flower diameter (8.35 cm), fresh weight (8.07 g) and field life (12.37 days) were observed in Karnool Pink. The longest flower stalk length (26.77 cm) and girth (1.49 cm) was found in KAU C-6. KAU C-4 recorded maximum duration of flowering (104.29 days), greatest number of flowers (96.95) and yield (0.31 kg) per plant. Longest shelf life was recorded in KAU C-7 (4.89 days) and vase life in KAU C-3 (14.48 days). The genotypes KAU C-4 and KAU C-6 can be recommended for both cut and loose flower purposes whereas the genotypes Karnool Pink, KAU C-1, KAU C-7, KAU C-3, KAU C-8 and KAU C-2 are best preferred for loose flower purpose and the genotype Pink Cloud was found ideal for both garden type and loose flower production under warm humid tropical plains of Kerala. [ABSTRACT FROM AUTHOR]

The study was conducted at department of Floriculture & Landscape Architecture, College of Agriculture, Vellanikkara, Kerala Agricultural University, Thrissur, to evaluate 20 marigold genotypes with 12 testers (10 African marigold (Tagetes erecta) and 2 French marigold (Tagetes patula) genotypes) and 8 lines for the production of F1 hybrids, during 2019-20 and 2020-21. Pooled data analysis of vegetative parameters showed the superiority of tester genotype KAU-M 21 in terms of plant height (43.77 cm), plant spread (31.97 cm), number of primary branches (7.87) and stem girth (4.12 cm), while KAU-M 1 showed the superiority in total leaf area (47.27 cm2). Among the lines, KAU-M 42 showed good performance for all the vegetative parameters. Analytical study on floral characters highlighted that the testers, KAU-M 1 and KAU-M 40, produced larger flowers (6.3 cm and 5.80 cm diameter) having significantly more individual flower weight (9.70 g and 7.85 g) and ray floret weight (5.60 g and 3.50 g) respectively. French marigold genotypes KAUM 48 and KAU-M 47 showed earliest bud initiation (17.92 and 19.37 days) and earlier flower opening (35 and 37.75 days). KAU-M 46 produced maximum number of flowers per plant (103.37), while KAU-M 2, KAU-M 1, KAU-M 19 and KAU-M 40 recorded maximum yield that ranged from 215 to 243 g/plant. Among the lines, KAU-M 6 recorded highest number of flowers and yield per plant (92.32 and 228.99 g) followed by KAU-M 5, KAU-M 16 and KAU-M 42. Among the testers, shelf life of flowers differed significantly and majority of the genotypes recorded a shelf life ranging from 2.0 to 2.67 days. The total carotenoid content was significantly higher in KAU-M 47 and KAU-M 48 (4.85 and 2.26 mg/g respectively) among the testers, and KAU-M 18 and KAU-M 42 (2.01 mg/g and 1.49 mg/g respectively) among the lines. KAU-M 1 and KAU-M 5 recorded the highest lutein content (102.3 mg/g and 62.3 mg/g) among the testers and lines, respectively. [ABSTRACT FROM AUTHOR]

Exacum bicolor (Roxb.) is an herbaceous perennial endemic to peninsular India and enlisted as an endangered plant species. Since a thorough insight into the reproductive biology of a species is necessary to aid conservation and crop improvement, the present study was formulated to assess the floral biology and reproductive behaviour of the plant. It was found that the bisexual flowers of this plant possess pollen grains that remain viable for nine days after anthesis exhibiting maximum viability on the first day of anthesis (84.61%) and 84.18 per cent viability on the previous day of anthesis. Stigma was found to be receptive upto four days after anthesis. Maximum seed weight per capsule (17.21 mg) was realised from flowers pollinated on the third day of flower opening. There was 100 per cent fruit set in flowers that were open pollinated as well as in the flowers which were either controlled out-crossed or self-pollinated under control. Fruit set was not observed on bagging the flowers to avoid natural out-crossing, and on open pollination. Hence, it became evident that Exacum bicolor (Roxb.) is primarily a cross-pollinated species, although no self-incompatibility mechanism operates in the species. Also, natural self-pollination is not favoured for procreation; reproduction via apomixis is absent in the species. [ABSTRACT FROM AUTHOR]

In vitro propagation in cocoa is a potential tool for the rapid multiplication of true to type plants. Single noded cuttings of 2-3 cm collected from the budded plants maintained in polyhouse were used as explants. The experiment was done in five varieties: CCRP 2, CCRP 6, CCRP 8, CCRP 15 and Scavina. The best surface sterilization of explants was achieved using Mancozeb 0.2 per cent for 30 minutes followed by Cefotxim 0.1% for 10 minutes and then ethyl alcohol 70 per cent for 3 minutes and mercuric chloride 0.1 per cent for 5 minutes. Axillary bud sprouting was induced in basal Woody Plant Media (WPM) fortified with 2- isopentinyl adenine (2ip) and Indole-3-Acetic Acid (IAA). The period of single shoot induction from leaf axils was lowest (8.41) in variety CCRP 15 in media WPM+2ip 1ppm+IAA 0.02ppm. Among the varieties, highest multiple shoot induction percentage (93.75%) was recorded in variety Scavina. [ABSTRACT FROM AUTHOR]

An investigation was conducted at the Department of Floriculture and Landscaping, College of Agriculture, Vellanikkara to evaluate the performance of China aster genotypes in tropical plains of Kerala. Ten genotypes of China aster viz., Arka Kamini, Arka Shashank, Arka Archana, Phule Ganesh White, Phule Ganesh Violet, Phule Ganesh Pink, Phule Ganesh Purple, AAC-1, Local Pink and Mat White were evaluated for vegetative, floral and post harvest characters. The greatest plant height (68.86 cm), number of primary branches (14.25), number of leaves (56.48), stem girth (11.09 cm) and plant spread (50.08 cm) were recorded in the variety Phule Ganesh Pink. Leaf area was highest in variety Phule Ganesh White (34.31 cm² ). Number of flowers per plant was the highest in variety Arka Shashank (20.20), while Arka Archana (18.47), Local Pink (18.47), Phule Ganesh Pink (17.73), Phule Ganesh White (16.93) and Arka Kamini (16.27) were on par. Flower stalk length was highest in variety Phule Ganesh Pink (21.39 cm), which was on par with Phule Ganesh Purple (20.61 cm), Phule Ganesh Violet (19.73 cm), AAC-1 (18.27 cm) and Phule Ganesh White (17.73 cm). Flower yield was highest in variety Phule Ganesh Pink (55.99 g). Duration of flowering was the longest in variety Local Pink (62.40 DAP) and was on par with variety Phule Ganesh Pink (60.60 DAP). Shelf life (3.67 days) and vase life (13.93 days) were the highest in variety Phule Ganesh Pink. The study revealed that Phule Ganesh Pink was best suited for cultivation in Kerala, both as cut flower and loose flower. The varieties Local Pink and Phule Ganesh White were also found promising for the tropical plains of Kerala. [ABSTRACT FROM AUTHOR]

A study was conducted at Department of Floriculture and Landscaping, College of Horticulture, Vellanikkara, to evaluate the performance of cut flower rose varieties and to select suitable varieties for commercial cultivation in Kerala. Three IIHR varieties viz., Arka Ivory, Arka Pride, and Arka Swadesh, and seven exotic rose varieties viz., Gold Strike, Noblesse, Revival, Taj Mahal, Corvette, Emma and Peach Avalanche were selected for the study. The varieties varied significantly with respect to various vegetative and floral parameters. The variety Taj Mahal was superior with respect to plant height (52.83 cm). Highest number of flowers were recorded in variety Revival (12.45) which was on par with Arka Ivory (11.38), Arka Swadesh (10.10) and Peach Avalanche (9.87). The variety Taj Mahal had highest number of petals (79.54). Vase life was highest for the varieties Revival (4.83 days), Taj Mahal (4.75 days) and Noblesse (4.75 days). The genetic estimates of heritability (%) and genetic advance (%) were found to be high for the characters fresh weight of flower, number of petals per flower and vase life, indicating that the expression of these characters were due to additive gene action. Varieties Taj Mahal and Noblesse, which were superior with respect to these characters, could be selected for further breeding programme. [ABSTRACT FROM AUTHOR]