NISCAIR Online Periodicals Repository Collection: IJBT Vol.08(2) [April 2009]

Acclimatization of neem microshoots adaptable to semi-sterile conditions

Title: Acclimatization of neem microshoots adaptable to semi-sterile conditions

Authors: Lavanya, M; Venkateshwarlu, B; Devi, B Poornasri

Abstract: The hardening of in vitro propagated microshoots of neem (Azadirachta indica A. Juss.) was carried out using 3 methods under semi-sterile conditions in low cost mini-polytunnels and a shade house. The percentage survival and rooting response was 16.25% in the first (2:1, v/v, sand and soil with 1′′ × 1′′ central cylindrical cocopeat plugs) and second method (1:1, v/v, cocopeat : bio-fertilizer), but was 100% in the third method (2:1, v/v, sand and soil with 1:1, v/v, cocopeat:biofertilizer and addition of Trichoderma viride. During the acclimatization process, the chlorophyll content in leaves gradually increased from 0.97 (stage I) to 1.35 (stage II), 1.56 (stage III) and 2.14 mg/g (stage IV), indicating a shift in the mode of nutrition from heterotrophic through myxotrophic to autotrophic. Similarly, the percentage water loss from the leaves of plantlets decreased from 90.38 (stage I) to 46.83% (stage IV), indicating stomatal development and progressive hardening. Ex vitro rooting and use of the bio-control agent could bring down the cost of production and make micropropagation of neem feasible and to be adopted as a rural enterprise.

Page(s): 218-222

Kappa-casein gene polymorphism in Indian goats

Title: Kappa-casein gene polymorphism in Indian goats

Authors: Kumar, A; Rout, P K; Mandal, A; Roy, R

Abstract: The present work was carried out to analyse the k-casein variants in five Indian goat breeds by SDS-PAGE, PCR-RFLP and SSCP method. A total of 152 unrelated blood samples and 102 milk samples belonging to Barbari, Beetal, Marwari, Surti and Local MP (non-descript) goats were used for analysis. SDS-PAGE exhibited k-casein allele A in all the breeds. Moreover PCR+RFLP analysis also confirmed the presence of AA genotype in all the breeds. PCR-SSCP analysis of k-casein genetic variant showed the k-casein A and B allele in the analysed samples. The k-casein A allele was the dominant variant found in all analyzed breeds with frequencies ranging from 0.70 (Barbari) to 0.8 (Local MP). The variant B was most frequent in Barbari goats as compared to other breeds.

Page(s): 214-217

STS marker based tracking of slow rusting Lr34 gene in Indian wheat genotypes

Title: STS marker based tracking of slow rusting Lr34 gene in Indian wheat genotypes

Authors: Priyamvada; Tiwari, Ratan; Saharan, M S; Chatrath, R; Siwach, Priyanka; Mishra, B

Abstract: Bi-allelic STS marker was used to confirm the presence of adult plant durable rust resistance gene Lr34 in advance generation breeding lines. These lines were scored for leaf rust three times at an equal interval and the area under disease progress curve (AUDPC) was calculated. The lower AUDPC values of Lr34 positive lines confirmed their slow rusting nature. In the absence of direct selection method, the breeders are selecting Lr34 gene carrying lines unintentionally as they showed better resistance. Lines possessing Lr34, an ‘undefeated gene’, should be used in breeding programme in order to have a broad-spectrum durable leaf rust resistance.

Page(s): 207-213

Microflora (fungal and bacterial) of selected terrestrial and marshy species of rhizosphere in response to spent wash treatments

Title: Microflora (fungal and bacterial) of selected terrestrial and marshy species of rhizosphere in response to spent wash treatments

Authors: Singh, P K; Sharma, K P

Abstract: In the present study, 16 fungal species were recorded in the rhizosphere of 4 terrestrial species [Acacia farnesiana (Linn.) Willd, A. leucophloea (Robx.) Willd, A. nilotica (Linn.) Del. and A. raddiana Savi] and 4 marshy species (Arundo donax Linn., Phragmites karka Steud, Typha angustata Bory & Chaub and Scirpus tuberosus Derf.) grown in tap water (control) and spent wash treatments (COD = 750-12,000 ppm). Their species richness was relatively higher (2-folds) in the spent wash treatments than their respective controls while their colony forming units were almost similar, exceeding in number to more than 300 units for a particular fungal species in the community. Aspergillus was the most dominant genus (4 species) followed by Fusarium (2 species) while the remaining 10 genera had one species each. The bacteria were Gram (+) bacilli and cocci arranged singly and in chains (also in bunches in cocci). In comparison to control, their CFU values were significantly higher (2-10-folds) in spent wash treatments, especially in the rhizosphere of marshy species.

Page(s): 240-243