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2018 - 201912020 - 20221
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Subject: Fruit Science × Author: AHIR, MEGHA ×
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    ThesisItemOpen Access
    SELECTION AND CHARACTERIZATION OF SUPERIOR GENOTYPES FROM SEEDLING TREE POPULATION OF WALNUT (Juglans regia L.) IN CHAMBA DISTRICT OF HIMACHAL PRADESH
    (UHF,NAUNI, 2022-10) AHIR, MEGHA; CHAUHAN, JITENDER K
    ABSTRACT The present study “Selection and characterization of superior genotypes from seedling tree population of walnut (Juglans regia L.) in Chamba district of Himachal Pradesh” aimed to assess the nature and magnitude of variability in walnut of existing plantations. On the basis of pre selection survey, a total of 98 healthy and bearing walnut genotypes were marked across walnut growing areas of Chamba district of Himachal Pradesh during 2019-2021. Marked trees were observed to be erect to semi-erect to spreading in growth habit, trunk girth, yield and yield efficiency varied between 53.15-422.55 cm, 3.44 to 57.93 kg/tree and 0.79-80.06 g/cm2, respectively. Low variation witnessed in various leaf characters. None of the marked trees was noticed to be lateral bearer. The physical nut and kernel characters like nut length, nut width, nut weight, shell thickness, shelling percenatage, thickness of dividing membranes, kernel weight, kernel length, kernel width and kernel percentage ranged from 29.30-48.64 mm, 27.91-39.66 mm, 9.73-23.34 g, 0.83-2.59 mm, 48.49-81.71 per cent, 0.13-3.18 mm, 2.82-9.26 g, 24.79-37.52 mm, 22.18-32.29 mm, 18.29-51.51 per cent, respectively among different walnut genotypes. High heritability with high value of genetic gain was obtained for yield efficiency and yield; with moderate genetic gain in kernel weight, shell thickness and nut weight in the genotypes under study which indicated that these characters were under the strong influence of additive gene action and hence simple selection procedure based on phenotypic expression of these traits would be more reliable. Maximum positive direct effect cited towards yield was contributed by kernel weight, nut width, nut length, leaf: leaflet width, shelling percentage, leaf: leaflet length, kernel percentage and thickness of dividing membranes. According to PCA, 6 principal components accounting for 83.46 per cent of total variance was extracted. Variables with high discriminating values including kernel weight, kernel percentage, kernel length, kernel width, nut length, nut width and nut weight were identified as the most useful variables for evaluation. On the basis of these variables, 9 superior genotypes were selected. On the whole, the present study has resulted in some elite walnut selections of indigenous origin representing a valuable genepool for use in future.
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    ThesisItemOpen Access
    CHARACTERIZING SOME GUAVA (Psidium guajava L.) CULTIVARS AND HYBRIDS
    (UHF, NAUNI, 2018-10) AHIR, MEGHA; KUMAR, KRISHAN
    ABSTRACT The present investigation entitled “Characterizing some guava (Psidium guajava L.) cultivars and hybrids” was carried out on eight years old stool layered nine guava cultivars and hybrids namely Punjab Hybrid-1, Punjab Hybrid-2, CISH-G-1, Lalit, Allahabad Safeda, CISH-G-4, Lucknow-49, Hisar Safeda and Hisar Surkha during the year 2016-17 and 2017-18 in RHR&TS, Dhaulakuan, Sirmour (H.P.), India. The experiment was laid out in a Randomized Block Design. These cultivars and hybrids were evaluated for their growth, foliage, floral, fruit, yield, biochemical and seed characters. The attitude of branches was observed to vary from erect to spreading to drooping. The anthocyanin colouration of young leaf was absent in Punjab Hybrid-2, Lucknow-49 and Hisar Safeda and present in rest of the cultivars and hybrids. Variation in leaf shape i.e. obtrullate, oblong and ovate; leaf apex shape i.e. apiculate and obtuse; leaf base shape i.e. rounded, obtuse and cordate were also observed. The flower initiation was found to be earliest in Lalit and Allahabad Safeda during both the years, whereas, CISH-G-1 and Hisar Safeda were the last. Fruit size and weight were observed maximum in Lalit which recorded highest fruit yield per tree but lowest yield efficiency. The fruit shape was observed to be ovate with pointed shape at stalk end in Punjab Hybrid-1, CISHG-4 and Lucknow-49, whereas in others were round in shape. The smooth fruit surface was observed in Punjab Hybrid-1, Allahabad Safeda and Hisar Surkha with longitudinal ridges in Lucknow-49, CISH-G-4 and Allahabad Safeda; longitudinal grooves in CISH-G-1, Lalit and Allahabad Safeda; conspicuous ridged collar around calyx cavity in Hisar Safeda. Flesh colour varied from yellow-white to greyed-yellow to orange-white to greyed-red. Maximum TSS, total sugars and reducing sugars were recorded in Hisar Safeda with minimum acidity. Lucknow-49 was observed to have minimum number of seeds. Fruits were found to be soft seeded in Hisar Surkha, CISH-G-1, Lalit and Allahabada Safeda were medium seeded and rest were hard seeded. From the present study it can be concluded that the development of descriptors will facilitate true identification and DUS testing of guava genotypes.