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The present study purports to assess the effect of Agrobacterium infection time, co-cultivation and cell density on in vitro response in hypocotyl explants of eggplant (brinjal) cv. Manjarigota. Agrobacterium(OD600 0.3-0.5) infection for 10-15 minutes (24.44±2.34%) was found to be optimum, while, higher or lower infection-time resulted in reduced callus initiation, shoot regeneration and explant survival. Explants with no (only Agrobacterium infection) or short (1 day) co-cultivation, showed reduced callus-initiation response and turned yellow, with no regeneration. Callus-initiation response increased from Day 1 (96.66±03.33%), and reached a maximum on Day 2 and Day 3 (100±00.00%). It decreased on further increase in co-cultivation time. Explants co-cultivated for three days showed highest regeneration response (30.00±02.96%) which thereafter reduced with further increase in co-cultivation time. Explants infected with Agrobacterium culture at 0.05 OD600 showed hardly any regeneration, and turned yellow and necrotic on the selection medium. Highest regeneration response (28.33±02.33%) was obtained in explants infected with 0.1 OD600 culture, and this gradually reduced as celldensity increased (upto 1.0 OD600), becoming zero in explants treated with cultures at 1.5 OD600 or above. Agrobacterium overgrowth was noticed on explants infected with cultures of 0.5 OD600 and above. Exposure of hypocotyl explants to higher cell-density, longer infection-time and prolonged co-cultivation regime resulted in severe necrosis of explants; time taken for development of Agrobacterium overgrowth was less with increase in the level of these factors. Regenerated shoots were healthy, green, elongated and showed root induction on culture medium containing Kanamycin.

An attempt was made to assess the effect of size, age and position of the explant, pre-culture and high cytokinin concentration in the pre-culture medium on shoot regeneration in brinjal hypocotyls co-cultivated with Agrobacterium. The study was carried out using hypocotyl explants of brinjal cv. Manjarigota, Agrobacterium strain A208 and shoot regeneration medium (full-strength basal MS medium, 2μM BAP + 0.05μM NAA, 3% sucrose and 0.8% agar) containing Cefotaxime (250-500mg l-1) and Kanamycin (100mg l-1). Hypocotyl explants showed callus initiation and shoot regeneration response after 10-12 and 20-22 days of culture, respectively. Five-day-old explants did not survive Agrobacterium infection, and ten-day-old explants showed higher shoot regeneration (29±1.91%) than older explants. Explants of medium size (1cm long; 32±2.62%) from the apical region (38.57±2.61%) showed better shootregeneration ability than explants of any other size or region. A period of four days of pre-culture (33.33±3.76) was optimal best for best shoot-regeneration in hypocotyl explants. No regeneration was seen in hypocotyl explants at shorter or longer pre-culture period. High cytokinin (10μM) in shoot regeneration medium during pre-culture enhanced shoot regeneration response (47.27±2.98%) in explants co-cultivated with Agrobacterium. Effects of various factors documented in this study will be useful in developing an efficient Agrobacterium-mediated transformation protocol in brinjal cv. Manjarigota.

In the present study, effect of size and age of hypocotyl explant on in vitro organogenetic responses was assessed in eggplant cv. Manjarigota. Size and age did not affect callus-initiation response, but showed marked influence on shoot regeneration response. Hypocotyl explants 1.5cm long showed highest shoot regeneration response (77.4%); either increase or decrease in size resulted in reduced response. Five to 15 day old hypocotyl explants showed direct shoot regeneration from cut ends, whereas 20-30 day old hypocotyl explants showed indirect shoot regeneration from callus produced on cut ends. Five day old explants were most responsive, with highest (91.23%) and thirty day old explants least responsive with reference to shoot regeneration response (20.85%). Shoot regeneration frequency decreased with increasing age, whereas shoot regeneration efficiency increased with increasing age of hypocotyl explants.

A field study was conducted during rabi season of 2003-2004 to evaluate the potential of statice cultivars as cut flower crop in the field of Department of Floriculture and Landscape Gardening, K.R.C. College of Horticulture, Arabhavi. The experiment was laid out as a Randomised Block Design with four replications. The panicles of each variety were harvested when calycys of individual flower have mostly opened and showing colour. The cultivar Turbo White recorded maximum plant height (21.78 cm), panicle length (80.94 cm), stem diameter (0.61 cm), no. of leaves (186.60), maximum fresh weight of panicles (530.09 g/plant), plant spread 62.15 cm2 and remained superior over others. The results are in agreement with the findings of Angadi (2000) in China aster. Maximum panicle production per plant (25.64) was recorded in cv. Turbo White, which was on par with the cultivar Turbo Carmine (22.54). The results were in line with the findings of Kumar et al. (1998) in annual statice Turbo White. The cultivar Turbo White was good in quality parameters by recording maximum panicle length, girth and number of branches per panicle. It was also vigorous in vegetative growth. Therefore, the cultivar could produce better quality panicles and found to be suitable for semi arid regions.

Effects of growth regulators and type of explants on transformation and in vitro morphogenetic responses of brinjal cv. Manjarigota were studied. Both hypocotyl and cotyledonary explants showed marked influence on in vitro morphogenetic responses after Agrobacterium co-cultivation. Hypocotyl explants showed callus initiation and regeneration responses earlier than cotyledonary leaves. Hypocotyl explants were found to be better than cotyledonary leaf explants in regenerating shoots after Agrobacterium co-cultivation. There was delay and reduction in both callus and regeneration responses in Agrobacterium co-cultivated explants. Hypocotyl explants showed the highest regeneration response on MS medium containing 2 μM BAP and 0.05 μM NAA while cotyledonary leaves did not show regeneration response after Agrobacterium co-cultivation. However, they showed green buds on MS medium containing 10 μM BAP and 1 μM NAA, which could not differentiate into shoots. Overall, hypocotyl explants were found better in regenerating shoots after Agrobacterium co-cultivation.

A study was conducted to find out the effect of antibiotics and gelling agents on Agrobacterium-mediated transformation using hypocotyl explants of brinjal cv. Manjarigota. Hypocotyl explants of brinjal were found to be sensitive even to the lowest level of kanamycin (25 mg/l) tested. Explants that showed increased callus initiation and regeneration response upon cocultivation with Agrobacterium and on kanamycin at 100 mg/l were selected as this indicated a highly effective selection pressure. Cefotaxime did not affect regeneration response and at 500 mg/l, it effectively inhibited Agrobacterium overgrowth completely on Agrobacterium cocultivated hypocotyl explants. There were marked differences in regeneration response in hypocotyl explants cultured on medium solidified with various gelling agents indicating the influence of gelling agent on the activity of kanamycin in culture medium, which indirectly affects selection and recovery of transformants. Antibiotics and gelling agents could therefore affect, directly or indirectly, transformation of brinjal cv. Manjarigota.

Poor regeneration is one of the limiting factors in the development of transgenic crops since Agrobacterium as a plant pathogen can disturb the fragile in vitro conditions with wounding and infection regimes. We have tried to optimize the transformation system in two important varieties of brinjal after Agrobacterium infection to the explants. The effect of explant was studied and hypocotyls were found to be better than cotyledonary leaves. High BAP during the preconditioning period was found to further enhance the regeneration rate. Therefore, use of hypocotyls and high BAP during preconditioning can improve the regeneration of transformed cells and recovery of transformants in vegetables especially brinjal.

Milk producers are facing "low fat and low Solids-Not-Fat (SNF)" problem very frequently especially during summer in crossbred cows in southern parts of India. Hence, this study was conducted to observe the effect of Saccharomyces cerevisiae1026 in early lactating Jersey crossbred dairy cows. The milk fat content of the yeast supplemented cows did not differ with control cows. The yeast supplemented cows showed no significant difference in dry matter intake, concentrate feed consumption, green and dry fodder consumption. [ABSTRACT FROM AUTHOR]

The article reflects on a study conducted on investigate the efforts of concentrate and urea molasses mineral block (UMMB) supplementation on the growth and carcass characteristics of Mecheri lambs form mutton production, wherein a growth trails method was performed. It reveals that the supplementation increased thebody weight of grazing lambs and UMMB was found to be versatile supplement for the growth of Mecheri spee.

The article presents research which assessed the feeding practices, feed and fodder resources available with the dairy farmers in Tamil Nadu, India. The researchers conducted a field survey and gathered necessary data from 150 farmers. They found that most of the respondents practiced individual feeding and nearly half of them used home mixed concentrate to enhance the digestibility of the nutrients to the animals.

The article presents a study on the composting of poultry waste with sugarcane top and coirpith waste. The researchers performed the dead birds composting experiment at the Department of Livestock Production and Management of the Veterinary College and Research Institute in Namakkal, India. They used several selective media including Salmonella Shigella agar for Salmonella, MacConkey agar for total coliform and nutrient agar for total bacterial count. They found that the Salmonella count did not significantly differ between various mixtures of treatment.

The article presents a study on the effect of microclimate on the physiological responses of Soviet Chinchilla and White Giant rabbits under two types of housing. The researchers observed 16 Soviet Chinchilla and 16 White Giant rabbits, which were divided into four groups. They recorded the climatic variables daily all throughout the experimental period, after which they recorded the rectal temperature of the rabbits in the morning and evening. They found that microclimatic variables in modern raised shed were significantly lower.