Fortnight Of January Research Articles

Effect of grow cover and sowing time on growth, yield and quality of muskmelon (Cucumis melo L.)

The present investigation entitled Effect of grow cover and sowing time on growth, yield and quality of muskmelon (Cucumis melo L.) was carried out at Instructional farm, Jambuvadi, College of Horticulture, Junagadh Agricultural University, Junagadh during 2022-23.The experiment was laid out in Randomized Block Design with Factorial Concept (FRBD) with two factors. The treatments consisted of five date of sowing i.e., second fortnight of December, first fortnight of January, Second fortnight of January, First fortnight of February and second fortnight of February under open field as wellas biodegradable low tunnel, respectively. The result clearly indicated that effect of the grow cover (biodegradable grow cover) and sowing time (1st fortnight of February) (G2S4) recorded minimum days to germination (5.20), days to flowering (22.40) and maximum vine length (139.53 cm), length of secondary branches vine-1 (121.92), fruit weight (538.33 g), polar diameter (9.50 cm), fruit yield vine-1 (1.80 kg vine-1), total fruit yield (76.44 t ha-1), pulp thickness (3.00 cm), TSS(8.11oBrix) and minimum cavity index (3.68cm).

Population Dynamics of Pod Borer <i>Helicoverpa armigera</i> (Hubner) on Chickpea

A field experiment was carried out to study the population dynamics of pod borer Helicoverpa armigera (Hubner) on chickpea at the Agronomy Farm, College of Agriculture, Swami Keshwanad Rajasthan Agricultural University, Bikaner during two consecutive seasons i.e. rabi 2021-22 and 2022-23. The incidence commenced from first and second week of December i.e. 49th and 50th Standard Metrological Week (SMW) and disappeared in the first fortnight of January. Incidence again started from the third week of January (3rd SMW) which increased gradually and reached peak (6.4 and 5.2 larvae/ m row) in the third and second week of February (8th and 9th SMW) during first and second season. These peaks coincided with the vegetative, flowering, and podding stages. The correlation studies showed that incidence has a positive significant correlation with temperatures (p<0.01) while, morning (r = -0.609 and -0.640, p<0.05) and evening relative humidity (r = -0.728, p<0.01 & -0.666, p<0.05) showed negative significant correlation. Further, stepwise linear regression model indicated that maximum temperature as single predicator independent variable had the strongest relationship with incidence based on high R2 value (61% and 63.40%). This forewarning regression model may help the farmers to take advance decision so as to minimize the damage caused by pod borer on chickpea.

Population Fluctuation of Gram Pod Borer in Rabi Pulses of West Bengal

During the rabi season of 2021-22, a field research has been carried out at BCKV [District Seed Farm (AB Block)] Kalyani, Nadia, West Bengal for studying the pattern of incidence of gram pod borer or tomato fruit borer (Helicoverpa armigera Hubn.) in relation with prevailing meteorological parameters and to record the population fluctuation in four rabi pulse crops, viz., chickpea (var. KWR 108 and JAKI 9218), fieldpea (var. Rachna and VL 42), lentil (var. IPL 220 and L 4727) and grasspea (var. Prateek and Ratan). During the vegetative stage of the fieldpea, the Helicoverpa population first emerged, then gradually increased and declined near maturity; in lentil and grasspea it was recorded from flowering stage and persisted until maturity; in chickpea it was noticed from pod formation stage and continued up to maturity. None of the weather variables were significantly correlated with the Helicoverpa larvae population recorded on fieldpea and lentil while, regression studies denote that maximum (Max. T) and minimum (Min. T) temperature exhibited the most impact on the occurrence of Helicoverpa in grasspea and chickpea, respectively. The comparative study revealed that, Helicoverpa first appeared on lentil and field pea during the first week of January; then population appeared on grasspea during the end of second fortnight of January. Occurrence of the pest was noticed on lentil, field pea and grasspea in January and February and after that the population shifted to grasspea, fieldpea and chickpea during February to March. Chickpea was the most preferred crop as the highest population observed on this crop coinciding with pod formation stage.

Constraints in Rice Fallow Pulses Production in Srikakulam District of Andhra Pradesh

Rice fallow cultivation constitutes the major portion of pulse production particularly black gram and green gram in Srikakulam district of A.P. Farmers are reaping lower yields of 3.75-5.00 q/ha against 15.0-20.0 q/ha of its potential. Keep this in view an extension study was conducted on the study of constraints and reasons for low productivity in Pulses in Srikakulam District. Ex-post-facto research design was used for the study with a total sample size of 60. Results revealed that the low soil fertility was the major constraint in pulses production (100%), the incidence of yellow vein mosaic virus (93.33), labour scarcity and incidence of low temperatures and fog during the flowering period i.e., the first fort night of January (88.33%), weed infestation particularly vicia, cuscuta. xanthium and Echinochloa (86.67%). Lack of YVMV resistant varieties and suitable varieties (83.33%) and lack of a regulated market (96.67%) were the major technical or situational constraints. Non-adoption of irrigation management (93.33%), non-adoption of seed treatment (91.67%), non -adoption of proper sowing (way of broadcast) method and seed rate (90.00), non-adoption of weed management practices (88.33%), non- adoption of foliar nutrient management in rice fallow pulses (86.67%) were the adoption gaps perceived as constraints. There is a need to conduct more Front Line Demonstrations (FLDs) in the farmer fields, more training programmes to the farmers and timely supply of inputs or make available to the farmers prior to the season.

Desempenho de variedades das uvas resistentes (PIWI), 'Felicia', 'Calardis Blanc' e 'Helios' produzidas em dois locais do estado de Santa Catarina (BR)

ABSTRACT Downy mildew (Plamopora viticola) is one of the major problems to produce wine grapes in Brazil, a main cause of yield losses in the Southern region of the country. An alternative to the use of pesticides is the use of resistant varieties (PIWI): wine grapes combining high oenological potential and resistance to diseases. The goal of this work was to assess the vegetative and productive performance and maturation of three PIWI varieties (‘Felicia’, ‘Calardis Blanc’ and ‘Helios’) produced at altitudes of 840m and 1250m in the 2020, 2021 and 2022 vintages. The study is focused on four phenological stages: budbreak (BBCH 7), full bloom (BBCH 65), veraison (BBCH 81) and maturity/harvest (BBCH 89). The criteria for measuring the productive performance were, the number of clusters, average cluster weight, production per plant, yield and Ravaz index. As parameters for technological and phenolic maturation, pH, soluble solids, total acidity and total polyphenols were evaluated. The budbreak occurred at the end of August until the second fortnight of September, the flowering occurred in the second week of October, the veraison occurred during the month of December, and the maturity/harvest occurred from the second fortnight of January until the beginning of February. The earliest budbreak occurred with ‘Felicia’ in the vineyard at 1250m and the latest occurred with ‘Calardis Blanc’. Regardless of the vineyard altitude, there was practically no difference in the flowering date between varieties and the vineyards altitude, the veraison and the maturity/harvest occurred earlier in the vineyard at 840m. The varieties produced at 840 m had a shorter cycle and proved to be more productive when compared to those produced at 1250 m. The studied varieties showed good phenological adaptation, high yield and maturation indices suitable for the production of quality still and sparkling white wines at both altitudes. From the results obtained, ‘Felicia’ and ‘Calardis Blanc’ seem to be the most promising varieties for cultivation in both altitude ranges.

Effect of Sowing Window and Phosphorus Levels on Growth and Yield of Summer Fodder Cowpea

Background: Cowpea [Vigna unguiculata (L.) Walp.] has emerged out as a potential crop for meeting the requirement of high quality fodder to fast expanding cattle population. There is a large gap between the demand and supply of green fodder during the lean period which can be narrowed down through the agronomic approaches. Among them, time of sowing and fertilizer application are considered to be the most important factors determining the production potential of the crop. Keeping this in view, the present investigation was taken up in order to find out the optimum time of sowing along with the optimum dose of phosphorus for the production of fodder cowpea. Methods: The present experiment was undertaken during summer, 2019 on sandy loam soils of dryland farm, S.V. Agricultural College, Tirupati. Three time of sowing viz., I fortnight (FN) of January, II FN of January and I FN of February assigned to main plots and four levels of phosphorus viz., 0, 20, 40 and 60 kg P2O5 allotted to subplots with three replications were maintained under split plot design. Result: The plant height, number of leaves plant-1, number of branches plant-1, dry-matter production and number of nodules plant-1, leaf to stem ratio and green fodder yield were higher with early sown crop i.e. I FN of January. Application of 60 kg P2O5 ha-1 resulted in significant improvement in the growth parameters, yield attributes and yield of fodder cowpea, while the lowest were recorded under control conditions (0 kg P2O5 ha-1). The interaction between time of sowing and phosphorus levels influencing the above parameters was found to be non-significant. In conclusion, the present investigation revealed that fodder cowpea gives optimum green fodder yield with high nutritional quality on sown during I FN of January with 60 kg P2O5 ha-1.

Incidence of Post-harvest Blue Mould Rot Disease of Indian Gooseberry (Emblica officinalis Goerth.) Incited by Penicillium islandicum Sopp.

Background: Aonla or Indian gooseberry (Emblica officinalis Goerth. Syn. Phyllanthus emblica L.) is one of the most important indigenous fruit of Indian sub-continent and cultivated since time immemorial. Amongst post-harvest diseases of aonla, blue mould rot caused by Penicillium islandicum Sopp. is most important as it affects the fruit yield and quality pertaining to the market value. Methods: A survey was conducted during November to January 2015-16 to assess the post-harvest practices and losses of Indian gooseberry in four locations of Hisar and Rewari districts of Haryana viz., CCS HAU Hisar orchard, terminal market of Hisar, Regional Research Station, Bawal orchard and terminal market of Rewari. Result: The survey carried out from first fortnight of November to last fortnight of January, 2015-16 revealed that the maximum per cent disease incidence (6 and 7.50%) due to blue mould rot was observed in terminal markets of Rewari and Hisar districts, respectively. The disease incidence was 7.0 and 6.25 per cent in fruits collected from orchards of CCS HAU, Hisar and RRS, Bawal respectively after 10 days of storage in laboratory. Some indigenous postharvest practices were observed being practiced in all the growing areas mostly by the growers and /or traders involved in harvesting.

First phenological and aerobiological assessment of olive orchards at the Northern limit of the Mediterranean bioclimatic area

An increase in the cultivation of olive trees was prompted in the Northwestern Spain during recent years favored by the agricultural politics in the region. The aim of this study is to know the phenological and aerobiological behavior of the olive trees at the northern limit of the Mediterranean bioclimatic area in order to determine their thermal requirements for the development of predictive agro-phenological models for two varieties (Arbequina and Frantoio) of the new olive cultivated areas. The BBCH scale was used for the phenological observations. Chill accumulation during dormancy and heat requirements to overcome the successive phenological stages were calculated following different methods. To complete the phenology predictive models, the Mitscherlich’s monomolecular equation was applied. The monitoring of the atmospheric pollen content was conducted by means a volumetric pollen Hirst trap placed in the middle of the plot. The period of chilling accumulation was completed during the first fortnight of January with an average of 654 chilling hours and a base temperature of 7.5 °C. Considering the duration of the vegetative olive cycle around 2390°GDD (growing degree days) was necessary to overcome the ripening of berries. The proposed model for the prediction of the successive ecological events showed a deviation between 1.5 and 3.5 days on the phenological scale. The presence of Olea pollen grains in the atmosphere of the olive grove was registered during stage 5 and stage 6 (flowering). The Hybrid Single Particle Lagrangian Integrated Trajectory Models confirmed that pollen peaks during the previous days to the flowering stage came from the extensive olive groves of the Northern Portugal which flowers some days in advance.

Crop Weather Relationships of Fodder Sorghum Varieties under Different Sowing Times in Southern Agro Climatic Zone of Andhra Pradesh

Field experiment was carried out during summer, 2018 at S. V. Agricultural College, Tirupati, Acharya N. G. Ranga Agricultural University to study the crop weather relationship of fodder sorghum varieties under different times of sowing. The experiment was in four dates of sowing (I Fortnight of January, II Fortnight of January, I Fortnight of February and II Fortnight of February) with varieties (CSV 21 F, CSV 30 F and CSV 32 F). Results are revealed that among the four times of sowing, different meteorological indices GDD, HTU, PTU, and TUE varied across the different growth stages. Early sowing (I Fortnight of January) had favorable agro-climatic conditions particularly temperature, day length and sunshine hours interms of required accumulation of GDD, PTU and HTU from sowing to harvest compared to other dates of sowing. Total requirement of accumulated GDD, HTU and PTU showed increasing trend with extension of sowing time from I Fortnight of January to II Fortnight of February. The CSV 32 F variety accumulated maximum GDD from sowing to until harvest.

Inheritance pattern of cold tolerance in pigeonpea [Cajanus cajan(L.) Millsp.

Among all the abiotic stresses, cold is one of the important factor limiting crop productivity. Medium and late maturing varieties cover most of the cultivated area of pigeonpea and therefore the chances of facing cold/frost are prominently high. Northern parts of the country are witnessing very low temperature during the last fort night of December and first fortnight of January, which is conducive for frost injury and the susceptible lines exhibit frost symptoms. Screening of 302 germplasm/lines of pigeonpea comprising of varieties and advance materials against frost injury during the years 2016-2018 facilitated to identify tolerant and susceptible lines. One hundred and forty one lines did not show any injury symptom, whereas 120 were classified under score 1 and 17 lines showed moderate symptoms to frost injury. A highly frost tolerant (insensitive) line ICP 10509 was crossed to susceptible (sensitive) line ICP 11182 to study the nature of frost injury and mode of inheritance. The F1 hybrid showed tolerance to frost injury with 1-2 leaves showing little symptom (score 0-1) indicating dominance of the trait. The F2 population segregated into tolerant (216 plants) and susceptible individuals (91 plants) fit well into expected ratio of 3(T): 1(S) (P value = 0.06027) signifying that frost tolerance (insensitivity) is controlled by a single dominant gene. The proposed hypothesis was verified by backcross populations; B1 (F1 x ICP 11182) segregating into 1(T):1(S) ratio (P value = 0.1237), whereas, all the plants in B2 (F1 x ICP 10509) generation exhibited tolerance to frost injury. The identification of a single gene exhibiting tolerance to frost injury may be useful for developing frost tolerant genotypes.

Study on varietal preferences and seasonal incidence of parasitoids of rice pests

The egg masses of yellow stem borer, larvae of leaf folder and rice horned caterpillar and eggs of ear head bug were collected randomly at fortnightly interval from four different varieties viz., CO 43, CO 50, CO 51 and CR 1009 from the rice field. The data was pooled and per cent parasitization was calculated to find out the varietal preference and seasonal variations of parasitoids. Among the four different varieties tested for the preference of parasitoids, per cent parasitization of stem borer egg mass was found to be more (26.59) in CO 50. The per cent parasitization of leaf folder larvae and rice horned caterpillar was found to be maximum in CO 51(40.29) and CO 43(33.21), respectively. In case of ear head bugs, the egg parasitization was maximum (27.70) in CO 50. The mean egg mass parasitization of stem borer was highest (71.88) in first fortnight of December. The larval parasitization of leaf folder and rice horned caterpillar were found to be maximum during the second fortnight of December (64.3) and the first fortnight of January (71.88), respectively. The parasitism rate of ear head bug eggs was maximum (62.95) during the second fortnight of December. Interestingly, phoresy exhibited by Sceliocerdo sp. an egg parasitoid of Neorthacris sp. was also recorded.

Population dynamics and new record of larval parasitoids, Senometopia sp. and Winthemia sumatrensis (Townsend) (Diptera: Tachinidae) on banana skipper, Erionota torus Evans (Lepidoptera: Hesperiidae) from South Karnataka

Field study was conducted for two years (2014-16) to know the population dynamics of banana skipper, Erionota torus Evans (Lepidoptera: Hesperiidae) and its tachinid parasitoids, Senometopia sp., and Winthemia sumatrensis . The pooled data over the two years indicated that the skipper plant infestation ranged from 6.66 to 84.25 per cent and incidence started during the first fortnight of August (8.34 per cent incidence) when the crop was at broadleaf follower stage, and a gradual increase in the infestation level of skipper was observed with a peak activity (84.25 per cent incidence) during first fort night of January (Pre flowering period) and also extended to the flowering period (February to March). The pooled data over the years indicated the maximum incidence was recorded during pre flowering period with a mean infestation of 75.02 per cent followed by flowering period (45.67 per cent), broad leaf followers (29.58 per cent) and bunch period (1.66 per cent). Two tachinid parasitoids Senometopia sp., and W. sumatrensis were encountered during our two years study period. The larval parasitoids activity initiated from second fortnight of September (0.62 per cent) and reached its maximum population during second fortnight of November (7.25 per cent) and later parasitoid activity gradually declined till second fortnight of January (0.62 per cent). The maximum activity was noticed during pre flowering period with a mean of 3.27 per cent parasitization by Senometopia sp., and W. sumatrensis .

Determination of heavy metal pollution index of ground water of village Wallipur in Ludhiana district

The objective of the study was to reveal the seasonal variations in the groundwater quality with respect to heavy metals contamination near Buddha Nullah in Ludhiana district. To get the extent of trace metals contamination, groundwater samples from tube wells were randomly collected from 16 different points on both sides along the course of Buddha Nullah from areas of Bhamian Kalan, Khasi Kalan and Wallipur Kalan villages of Ludhiana district during first fortnight of June (Pre-monsoon), first fortnight of November (Post-monsoon) and first fortnight of January (Winter season) during the year 2013-14. The concentrations of toxic and heavy metals such as metalloids B, As, Pb; alkaline earth metals Mg, Ca; alkali metals Na, K; transition metals Cr, Mn, Fe, Cu, Zn, Cd and nonmetal S were determined. The heavy metal pollution index (HPI) was calculated. Most of the parameters were found within permissible limit of BIS, 2004. The average values of concentration of Ca, Cr, Mn, As and Pb for pre-monsoon season was higher than average concentration of post-monsoon and winter season. Overall HPI calculated based on the mean concentration of the heavy metals was found to be 18.11, 15.32 and 16.10 for pre-monsoon, post-monsoon and winter season, respectively, which was below the critical pollution index value of 100. The study recommended proper treatment to the sewage water which is being discharged into the Buddha Nullah.

Evaluation of different doses of indole-3-butyric acid (IBA) on the rooting, survival and vegetative growth performance of hardwood cuttings of Flordaguard peach (Prunus persica L. Batch)

The present study was conducted on the evaluation of different doses of indole-3-butyric acid (IBA) on the rooting, survival and vegetative growth performance of hardwood cuttings of Flordaguard peach (Prunus persica L. Batch) during the years 2012-13 and 2013-14 at Punjab Agricultural University, Regional Research Station, Gurdaspur. The hardwood cuttings of 10 years old Flordaguard peach plant having 15-20cm in length and 0.8-1.2cm in diameter with 6-7 buds were prepared in the first fortnight of January .The basal portion of the cuttings was dipped in different doses of IBA viz. 1000ppm, 2000ppm, 3000ppm, 4000pppm, 5000ppm and control (without IBA treatment) for 1-2 minutes and planted in an open field conditions by following the recommended cultural practices for nursery raising. It was noticed that hardwood cuttings of Flordaguard peach treated with 3000ppm of IBA for 1- 2 minutes significantly took the minimum number of days to sprouting (7.05), rooting (6.0) with highest sprouting percentage (98.45%), survival percentage (90.55%), plant height(195.45cm), plant girth(10.50cm), number of branches(13.50) ,number of leaves (260.4), leaf length (19.55cm), leaf breadth (4.12cm), leaf weight (2.0gm), per-cent rooting (94.45%), number of roots (75.83), root length (38.0cm), root girth (0.98 cm) and root weight (13.50gm).Therefore, the application of 3000 ppm IBA was found to be best in terms of rooting, survival and vegeta-tive growth of hardwood cuttings of Flordaguard peach (Prunus persicaL. Batch). The beneficial effect of present work develop protocol which can be reliably used to develop the rootstock plant of Flordaguard which is resistant to nematodes through cutting which become ready for budding/grafting in the field in one year instead of two years as raised through seed

Field Experiment on the Assessment of Natural Enemy Population in Different Rice Varieties under Natural and Protected Conditions

Field Experiment on the Assessment of Natural Enemy Population in Different Rice Varieties under Natural and Protected Conditions A field experiment was conducted to assess the natural enemy population viz., parasitoids and predators between the natural and protected conditions in different popularly grown rice varieties viz., Seeraga samba, CO 43, ASD 16, BPT 5204 and ADT 37. The mean data of the natural enemies of five different varieties revealed that under natural condition, more number of natural enemies was recorded in the variety ASD 16 (28.00 nos./sweep) followed by BPT 5204 (26.88 nos./sweep), CO 43 (26.55 nos./ sweep), Seeraga samba (25.63 nos./sweep) and ADT 37 (23.23 nos./sweep). In protected condition, the natural enemy population was less compared to the natural condition. The variety, ASD 16 harboured more number of natural enemies of 21.45 number/sweep followed by BPT 5204 (21.28 nos./sweep), CO 43 (21.05 nos./ sweep), Seeraga samba (19.63 nos./sweep) and ADT 37 (19.05 nos./sweep) in protected condition. During the second fortnight of February 2015, the maximum number of natural enemies was recorded to the tune of 156.9 nos./sweep and 127.3 nos./sweep in both the conditions. Minimum number of 107.4 nos./sweep and 81.5 nos./sweep was recorded during first fortnight of January 2015 under natural condition and protected conditions respectively...

Impact assessment of intra seasonal temperature variations on wheat yield using CERES Wheat model

A field experiment was conducted at Ranchi (Jharkhand) during rabi season of 2009-10 to 2011-12 with wheat cultivar K 9107 sown on three dates (Nov 20,Dec 5 and Dec 20) to calibrate and validate the CERES-wheat model. There was a good agreement between simulated and observed wheat yields, days to anthesis and days to maturity. The validated model was used to study the impact of intra seasonal temperature variation on wheat. The sensitivity analysis of CERES wheat model, with respect to temperature variations and wheat yield, revealed that increase in temperature above the normal values to 3 oC, showed considerable yield reduction (12- 17 per cent) under different sowing dates. Similarly, with decrease in seasonal temperature up to 3oC, the yield enhancement by 12-16 per cent was observed. Sensitivity of CERES wheat model to incremental units of intra seasonal temperature showed a gradual decrease in yield as well as days to maturity under varied sowing dates. Increase in temperature ( 3 oC from normal) during 2nd fortnight of January (16-31st ) was observed to be the most detrimental for wheat crop with respect to its yield for timely sowing date (20thNov) whereas it would be maximum during 2nd fortnight of February (15-28th) for moderately normal sown (5th Nov) and late sown crops (20thDec).

Weather based forewarning models for coffee berry borer and shot hole borer in Wayanad, Kerala

Pest damage due to coffee berry borer and shot hole borer in coffee plantations in Regional Coffee Research Station, Chundale and data on weather parameters were recorded during 1977 to 2007 (30 years). These long- term data on the pest damage and weather parameters were utilized to study the influence of weather variables on coffee berry and shot hole borer incidence with a view to develop weather based forewarning models for coffee berry borer and shot hole borer damage in Wayanad. The damage of coffee berry borer (CBB) was observed to be significant during January to March while the damage of shot hole borer (SHB) was spread during January to April and October to December. Highest percent damage of coffee berry borer and shot hole borer was observed during first fortnight of January. Maximum damage due to coffee berry borer was observed during 1982 and maximum damage due to shot hole borer was observed in 1994. Maximum temperature recorded during the first fortnight of January is predominant weather variable determining infestation of shot hole borer during first fortnight of January. Harvest and budding stages of the crop suffered heavy incidence of coffee berry borer and shot hole borer, respectively.

Effect of different treatments of Indole-3-butyric acid (IBA) on the rooting and growth performance of hardwood cuttings of peach (Prunus persicaL. Batch)

The present investigation was conducted on the rooting of the hardwood cuttings of Shan-i- Punjab Peach with the different treatments of Indole-3-butyric acid (IBA) during the years 2011-12 and 2012-13 at PAU, Regional Research Station, Gurdaspur. The hardwood cuttings of 15-20cm length and 0.8-1.2cm diameter having 5-6 buds were prepared from the dormant twigs of the 8-10 years old peach plants in the first fortnight of January .The basal portion of the cuttings was dipped in different doses of IBA viz. 1000ppm, 2000ppm, 3000ppm, 4000pppm, 5000ppm and control(without IBA treatment) for 1-2 minutes and planted in open field conditions by following the recommended cultural practices for nursery raising. It was observed that hardwood cuttings of peach cv. Shan-i-Punjab treated with 3000ppm of IBA for 1-2 minutes took significantly the minimum number of days to sprouting with the highest sprouting percentage, survival percentage, average number of roots, length of main root, root girth, root weight, plant height, plant girth, number of branches ,number of leaves and leaf area. Therefore, by following this treatment, the plants produced from the hardwood cuttings became ready for transplanting in the field in one year instead of two years in case of grafting and there was no chance of graft in-compatability.

Parasitization preference of Diaeretiella rapae (Hymenoptera: Braconidae) among different aphids in vegetable ecosystem

Solitary, polyphagous, endoparasitoid Diaeretiella rapae (Mc’Intosh) is considered as one of the prominent parasitoid of aphids on several host plants under natural field conditions. However, knowledge about its affinity and host preference towards different prey aphids is very scanty. So the present study on host preference of D. rapae revealed differential response for its parasitization to different aphid species infesting vegetable crops. It preferred maximum to cruciferous aphids, viz. Myzus persicae (59%) followed by Brevicoryne brassicae (51%) and Lipaphis erysimi (46%) than the other vegetable aphids like Aphis craccivora (23.67%) and Aphis spiraecola (19.67%). Seasonal incidence of D. rapae also indicated that its first occurrence was observed on M. persicae (13.67%) and L. erysimi (5.67%) during second fortnight of January, 2013 whereas spiraecola feeding on brinjal parasitized last indicating the preference of cruciferous aphids over other vegetable aphids. However, among the cruciferous aphids, highest parasitoid emergence was observed from L. erysimi (88%) followed by B. brassicae (81%) and M. persicae (80%). Comparatively higher body size (2.81 ± 0.23 mm) and tibial length (0.51 ± 0.05 mm) of M. persicae by the parasitoid for its parasitization and variation in nutritional quality in L. erysimi as food substrate towards D. rapae for its higher emergence might be responsible for their preference over the other host aphids.

Effect of Time of Fruit/Seed Collection on the Seed Germination of Grewia Optiva Drumm.

An experimental trial was conducted to study the effect of time of fruit/seed collection on the germination of Grewia optiva seeds- an important multipurpose tree species. The seeds of Grewia optiva (Beul) were collected on 15 days interval (Fortnightly basis) starting from 1st October, 2013 to 31st January, 2014 from the established open pollinated Seedling Seed Orchard during July, 2000, which is comprised of 60 families planted in three replications in randomized block design at a spacing of 2x2 meter. The seeds collected during different harvest dates were considered as treatments and were subjected to germination testing without any pre-sowing treatments to study the effect of time of collection on germination of Grewia optiva seeds. Significant differences were observed in germination percentage, moisture content of seeds in Grewia optiva collected during different collection period. The study indicated that optimum time of seed collection in Grewia optiva is found to be best between first fortnight, second fortnight of December and first fortnight of January as the seed collected during this period recorded maximum germination i.e. 86.66%, 80.00% and 80.00% whereas, seeds collected during first fortnight of October recorded minimum i.e. 20.00 percent germination. The study further indicates that optimum time of seed collection in Grewia optiva is found to be between first fortnight, second fortnight of December and first fortnight of January as the seed collected during this period recorded maximum germination percent as compared to other collection times taken in the study.