ThesisItem Open AccessChanges in antioxidant phytochemicals of turmeric at different stages of harvesting(College of Post Graduate Studies in Agricultural Sciences, CAU-Imphal, Umiam, 2009) Sangma, Sanyang A.; Jha, Anjani KumarAn experiment was conducted at ICAR Research Complex for NEH Region, Umiam, Meghalaya during 2008-2009 to study the changes in antioxidant phytochemicals of 12 turmeric varieties at different stages of harvesting (150, 180, 210 and 240 DAP). The highest yield per plant was recorded in the variety Megha Turmeric (692.67 g), the highest harvest index (95.30 %) and moisture content (92.70 %) was recorded from the variety Narendra Haldi while the variety Alleppy Supreme recorded highest (11.80 %) curcumin content. The maximum curing percentage (23.20 %) was observed in Kedaram and the maximum ascorbic acid content (57.87 mg/lOOg) was recorded from the variety Kasturi Tanaka and β carotene content was highest (4332.70 mg/100g) in the variety Kedaram. The colour value was measured using Hunter Lab Color Quest XE Colorimeter where the lightness (L) value was highest in the variety Jorhat Local (59.82), redness (a) value was recorded highest from the variety Kedaram (41.98) while maximum yellowness (b) value was observed highest in the variety Jorhat Local (34.82) and the maximum color difference (ΔE) was recorded from the variety Lakadong (6.96). The total phenol content was recorded highest (266.33 mg/100g) in the variety Alleppy Supreme and the antioxidant activity (FRAP) and (BCO) were recorded highest in the varieties Alleppy Supreme (16.60 umol Trolox/g) and Jorhat Local (89.01%), respectively. In correlation studies, no significant and positive correlation was observed between curcumin content and antioxidant activity. ThesisItem Open AccessPhysico-chemical changes of Sohshang (Elaenus latifolia L.) at different stages of maturity and storage(College of Post Graduate Studies in Agricultural Sciences, CAU-Imphal, Umiam, 2009) Lamare, Ridakini; Deka, Bidyut C.Sohshang (Elaegnus latifolia L.) belonging to the family Elaegnaceae is an important indigenous fruit of Meghalaya besides other places like Sibsagar in Assam and Naga Hills. It is mostly grown in semi wild condition in the backyard gardens of the region. Over the years, people have found many uses for Sohshang besides enjoying it as fresh fruits. These include homemade pickles, jam and chutney. However, fruits are quite astringent and acidic in taste when harvested at an immature stage while they are very soft when harvested at an over ripe stage which lead to poor quality of the fruits. Due to its high perishability in nature, fruits can be stored only for 2 to 3 days under open condition. In peak season, a huge quantity of the produce gets damaged during the process of handling, transportation and marketing due to number of reasons. Keeping these in view, a study was conducted to determine the physico-chemical changes of Sohshang at different stages of maturity and to evaluate the suitable packaging materials for shelf life extension of the fruit. For determining the optimum stage of harvesting, physico-chemical changes were determined at 15 days interval from fruits set to mature green stage and at 5 days interval from mature green stage to full ripe stage. On the other hand, for evaluation of suitable packaging materials during storage, physico-chemical changes were determined at 3 days intervals using perforated and non perforated PP, LDPE and DHM, leaf and control. In the present investigation, it was found that fruits harvested at 75 to 80 days after fruit set (DAF) developed acceptable physico-chemical qualities with good colour, flavour and texture. The study further revealed that days taken from fruit set to ripening (75-80 DAF), colour change (deep orange to pink), TSS (> 11) and TSS: Acidity ratio (>3) may be considered as the most reliable maturity indices for taking harvest decision of Sohshang fruit. On the other hand, changes in physico-chemical properties of the fruits were observed with the advancement of storage period irrespective of the packaging materials. However, the rate of change in packed fruit was comparatively slower as compared to that of control fruits. The present study revealed that packaging of fruits in non perforated PP had distinct advantages over control and other packaging materials in respect of shelf life extension besides preservation of quality and nutritional value of the fruits. Sohshang can be stored only up to 3 days in open condition whereas extension of shelf life up to 9 days is possible by packing the fruits in non perforated PP. Thus, it may be inferred that harvesting of Sohshang at 75 to 80 days after fruit set and packaging of fruits in non perforated PP could be suggested for obtaining the optimum and desirable qualities of the fruits with a better shelf life. ThesisItem Open AccessEco-biology and management of citrus leaf miner: Phyllocnistis Citrella ( Stainton) in Meghalaya(College of Post Graduate Studies in Agricultural Sciences, CAU-Imphal, Umiam, 2009) Syngkon, Shembha; Thakur, N. S. AzadSeasonal incidence of citrus leaf miner (Phyllocnistis citrella) was studied on ten infested citrus plants by recording number of miners on ten infested twigs from each plant, in the citrus orchard during 2008. The incidence of the pest was first noticed in the third week of February (2.67 %) and it reached its peak in the third week of August (31.5%). The pest was not observed from second week of December onwards till second week of February. The biology of P. citrella was carried out under the net house conditions in different months. The duration of various stages of P. citrella was shortest during July 15 to August 15 and longest during November 6 to December 16. The incubation, larval, pupal and total developmental period (egg to adult emergence) ranged from 2-8 days, 4-12 days, and 5-17 days and 11-33 days, respectively. Adult male and female longevity was found to be 3-10 days and 4-12 days, respectively. Fecundity ranged from 27.23 to 47.10 eggs/female, egg hatching from 27.23 to 47.10% and larval mortality from 22.42 to 33.91% in different months. The average sex ratio was found to be 1.37: 1 (female: male). Amongst the abiotic factors, temperature was found to favour the incidence and development of P. citrella. The management with different pesticides along with botanicals revealed that amongst the synthetic insecticides, imidacloprid (0.075 %) was the most effective in reducing larval population and per cent infestation, followed by monochrotophos, spinosad, endosulfan and lamdacyhalothrin in their order of efficacy, whereas amongst the botanicals karanjin (2 %) was found to be the most effective followed by azadirachtin 300 ppm and neem EC, however, prithvi garlic gold was found to be the least effective.. ThesisItem Open AccessStudies on the biology of Callosobruchus chinensis (linn.) on different pulses and its management at medium altitude hills of Meghalaya(College of Post Graduate Studies in Agricultural Sciences, CAU-Imphal, Umiam, 2009) Debbarma, Jash Paul; Thakur, N. S. AzadAn investigation was carried out on the biology of Callosobruchus chinensis (Linnaeus) on different pulses and its management in the laboratory of the Division of Entomology. ICAR Research Complex for North Eastern Hill (NEH) Region. Umlam. Meghalaya. The growth and development of C.chinensis was studied on nine different pulses and it was observed that there was highly significant difference between egg laying and adult emergence, longevity of the offspring and developmental period indicating difference in the suitability of different pulses on the growth and population build up of pulse beetle The most suitable hosts were found to be pigeon pea, cowpea, green gram and Kabuli chana where the adult emergence was higher compared to other pulses. French bean was found to be totally unsuitable for the growth as there was no adult emergence observed. The management of with different plant leaf powders revealed that among neem. lantana. melia. eupatorium and ageratum leaf powders, neem powder was found to be most effective in reducing egg laying, adult emergence and percent weight loss treated at the rate of 50g/kg green gram seeds. Lantana and eupatorium leaf powders were least effective. Among the oils, neem, mustard, sunflower and safflower oils at the rate of 5ml/kg seed was found to be most effective in the management of C.chinensis on green gram where no adult emergence was observed. Whereas adult emergence was observed in coconut. soybean and groundnut oil treated seeds at same rate of application Neem oil was found effective even at the lower dosage of 25ml/kg. Therefore, for the management of C chinensis, oils were more effective than the botanical powders. Any of the above mentioned oils could be used at the rate of 5m/1kg except neem oil which could be used even at 2.5 ml/kg. But oils are costlier than the powders and they are easily available. Therefore, powders of neem melia and ageratum leaves also could be used for the management of this beetle. ThesisItem Open AccessEco-friendly management of late blight [ Phytophthora Infestans,(Mont.) De Bary] of tomato in hill conditions of Meghalaya(College of Post Graduate Studies in Agricultural Sciences, CAU-Imphal, Umiam, 2009) Dkhar, Mariana; Dutta, RamThe present investigation was carried out for two consecutive years (2007-08 & 2008-09), which included study of Phytophthora infestans incidence at various growth stages of tomato, screening of 12 tomato genotypes for resistance /tolerance and evaluation of three bio-control agcnts/ two botanicals and four fungicides for management of late blight of tomato. There were significant differences in respect of disease rating and yield in both the cropping seasons. Among genotypes. CO-3 was found moderately susceptible and Rocky as highly susceptible. Whereas, rest of the genotypes were susceptible having varying degree of susceptibility, under mid-hill conditions of Meghalaya. The yield among botanicals evaluated. MATW-2 (native organic formulation) was found effective in managing the disease being next to fungicide, Ridomil MZ 72. Among Bio-control agents, the highest disease management was received by Nisarga compared to control. In in-vitro evaluation of botanicals bio-control agents and fungicides, the medium amended with MATW-2 reduced the maximum mycelial growth among botanicals, Nisarga among bio-control agents and Ridomil MZ 72 among fungicides, in terms of radial growth (cm). It was concluded from the study) that genotype CO-3 was found promising for cultivation in mid-hill conditions of Meghalaya and botanical MATW-2 in reducing the disease as well as enhancing the yield, hence, may be recommended for the management of late blight of tomato. ThesisItem Open AccessOff-season production of strawberry : effect of low tunnel and planting time(CPGS, CAU, Imphal, 2009) Syndor, Agreesia; Singh, AkathThe experiment was conducted at the Horticulture research farm of ICAR Research Complex for NEH region, Umiam, Meghalaya, India, during the year 2008-2009 to study “Off-season production of Strawberry: Effect of Low tunnel and planting time.” The experiment was laid out in a split plot design, the main plot being the time of planting (July, August, September, October and November)while low tunnel covers (UVS polythene, Shade net 50%, Shade net 75% and open condition)being considered in the sub-plot and were replicated thrice. The maximum growth in term of plant height and number of leaves was recorded during September planting while maximum plant survival percentage, chlorophyll contents, fruit set, yield, maximum berry size, berry weight were recorded in October planting. Among the low tunnel covers, low tunnel of 50% shade net was observed highest survival percentage, highest chlorophyll content, highest number of flowers, highest fruit set, highest yield, berry of heavy weight and better texture. Maximum plant height, numbers of leaves, earliness in flower production, maximum berry size were observed under UVS polythene tunnel. Earliest fruit set, firmer texture berry was recorded in the month of November and planting under UVS polythene in the same month was found to take minimum days to start flowering. Planting time significantly affected the chemical composition of strawberry fruit in which October planting observed to contained highest TSS and Beta –carotene, whereas sugars and total mineral content was observed during August planting while highest anthocyanin content and ascorbic acid content were recorded during November planting. Maximum TSS, ascorbic acid and anthocyanin were recorded under UVS polythene tunnel. Planting under UVS polythene tunnel in November recorded highest TSS whereas, highest ascorbic acid and anthocyanin content were obtained under the same tunnel in the month of October. Highest total sugar was also recorded under UVS polythene tunnel when planted in the month of August. Beta-carotene content was highest in the month of October under 75% shade net while total mineral was highest when planted in 50% shade net tunnel in the month of July. Fruit harvested from November planting can be stored for longer period. The occurrence of diseases was observed but it was not severe. From the present investigation, it was concluded that low tunnel structure and planting time had a positive effect on the plant growth, early fruiting, extension of fruiting period yield, quality and strawberry can be produced 30-35 days earlier than normal period when planted in low tunnels of 50% shade net in the month of July or August and the period of fruit availability may be extended to 47 days from normal when planted in the month of November under UVS polythene tunnel. ThesisItem Open AccessEFFECTS OF IN-SITU RESIDUE MANAGEMENT ON CARRY OVER SOIL MOISTURE CONSERVATION PRACTICES AND GROWTH AND PRODUCTIVITY OF MUSTARD (Brassica campestris) IN MID-HILL ALTITUDE(College of PG Studies, Central Agricultural University, Imphal., 2009) Kharkrang, Enboklang; Ghosh, P. K.The field experiment was conducted at the Water Management field, ICAR Research Complex for NEH Region, Umiam during the year 2008-09 to study the effect of in-situ residue management on carry over soil moisture conservation practices and growth and productivity of mustard (Brassica campestris) in mid-hill altitude. The experiment was laid out in Split Plot design with two main plot treatments, six sub-plot treatments and replicated thrice. The main plot treatments were conventional tillage and zero tillage. The sub-plot treatments consisted of different combinations of mulching materials, comprising maize stalk, Ambrosia weed biomass, FYM and poultry manure, which are tried for their moisture conservation abilities. In general, the soil moisture was higher under zero tillage than conventional tillage. Zero tillage also increased the soil temperature and soil organic carbon (OC). Adoption of FYM @10 t/ha + maize stalk cover (MSC) poultry manure @5t/ha + Ambrosia @5 t/ha + MSC or Ambrosia @10 t/ha +MSC proved to be more efficient than other organic materials, regardless of the tillage. Further, all the mulching treatment improved the soil physical properties and resulted in much better yield than the control. The Bulk densities of surface (0-15 cm) soils during the growing season of both maize and mustard crops were significantly affected by different conservation measures. In general, available Nitrogen (N) and potassium (K) was found to be higher in the conventional tillage plots, but the amount of available phosphorous was higher in the zero tillage system. In terms of yield, the mulching practices (maize stalk with or without Ambrosia) performed better and produced 1.5 to 4.5 times higher yield than the control. The improvement in the crop performance was evident from the difference of the treated plots, when compared with the control, where the lack of moisture caused lower growth, branching and pod formation leading to lower biomass and relative turgidity. Taking the economics of cultivation into consideration, Ambrosia@ 10t/ha was found to be superior to all the other treatments, for both the tillage system.