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Cololejeunea chenii Tixier, is reported for the first time from India. A detailed taxonomic description along with line drawing plate is provided for its easy identification.

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The CERES-rice model (version 4.0) was calibrated and validated using the data from a field experiment carried out during the rainy season of 2004 and 2005 at Shalimar, Srinagar (35° 5′ N latitude and 74° 89′ E longitude, 1587 m above the mean sea level, India. The experiment included six rice cultivars each transplanted on 25 May, 10 June and 25 June. Data of 25 May transplanting was used for model calibration and development of the genetic coefficients of the rice cultivars. The predicted and observed dates of phenological events were in close agreement with root mean square error (RMSE), mean absolute error (MAE) and D-index of 5.0 days, 4.3 days and 0.91, respectively, for anthesis and 3.7 days, 3.1 days and 0.91, respectively, for physiological maturity of the crop. The predicted and observed grain yields were also very close with a RMSE of 0.63 Mg ha −1 , MAE of 0.58 Mg ha −1 and D-index of 0.89, respectively. Corresponding values for above ground biomass was 1.17 Mg ha −1 , 1.01 Mg ha −1 and 0.82. Sensitivity test showed that simulated yield responded to temperature and atmospheric CO 2 concentration. Nitrogen 240 kg ha −1 at 25 May transplanting, recorded highest simulated grain yield (9.71 Mg ha −1 ). Further, 3 seedlings hill −1 produced highest simulated grain yield. The results suggest that the model can be applied in the temperate Kashmir to estimate crop productivity and optimize the management practices.

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The outcome of various solvent extraction (water, methanol, acidic 50% methanol, 70% acetone, acidic 50% methanol followed by 70% acetone) on the total phenolic content (TPC) and antioxidant capacity of fruit pulp, seeds, leaves and stem bark of seabuckthorn (Hippophae rhamnoides L.) was investigated. The seabuckthorn extracts possess high phenolic content, 1666–13769 mg GAE/100 g d.w. The mean TPC was found highest in seeds (11148) followed by stem bark (10469), leaves (6330) and pulp (3579 mg GAE/100 g d.w.). In general, the 70% acetone and acidic 50% methanol followed by 70% acetone extracts was found to contain significantly higher TPC than those obtained in other extracting solvents. Antioxidant capacity in terms of IC50 value of pulp (3.39 mg ml−1) was up to 7.8 times higher than those reported for stem bark (0.43 mg ml−1) and up to 2.4 times higher than those found in seeds (1.4 mg ml−1). Further, antioxidant capacity by FRAP assay showed that the stem bark possess maximum antioxidant capacity (16.83) followed by seeds (15.26), leaves (12.73) and pulp (12.61), all as mM FeSO4. Significant correlation was found between TPC and antioxidant capacity by DPPH and FRAP assays.

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Biochemical basis of disease resistance was studied by analysis of total phenols, peroxidase and ß-1,3-glucanase activities in calli of Fusarium wilt resistant and susceptible genotypes and one in vitro selected resistant cell line of chickpea (Cicer arietinum L.). The callus growth of cvs. JG62, C235 and WR315 was completely inhibited at 2% (v/v) concentration of culture filtrate of the fungus, whereas, the callus growth of in vitro selected resistant cell line FWR was not inhibited even at 4% (v/v) concentration of culture filtrate, indicating that a cultivar resistant under field conditions could show susceptibility under in vitro conditions. Total phenols were more in the resistant cell line than in the susceptible cultivars. However, increase in phenolics was higher in resistant cell line than in susceptible cultivars after treatment with the cultural filtrate, indicating that phenols reach an inhibitory level to the fungus in the resistant cell line. Peroxidase followed a similar pattern. Increase in ß-1,3-glucanase activity, after treatment, was higher in resistant cell line than in susceptible cultivars. Role of total phenols, peroxidase and ß-1,3-glucanase in defense against Fusarium wilt disease of chickpea is discussed.

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The analysis of the genotype × environmental interaction, which indicates the stability of genotypes, has always been part of plant breeding programmes before the release of varieties for commercial cultivation. In the present investigation the stability of seed yield, opium yield and morphine content in 11 advanced breeding lines of opium poppy was evaluated over five years. Combined ANOVA showed that both the main effects and interactions were significant, indicating the presence of genotype × environment interactions. The average seed yield and opium yield ranged from 10.41–16.92 q/ha and 45.21–59.85 kg/ha, respectively. Stability analysis involving the parameters bi, S 2 di, λi, s 2 , δ 2 , Wi, r 2 and CV identified four genotypes (BR330, BR333, BR229 and BR243) as ideal and stable for the traits studied. The level of association among different parameters obtained using Spearman’s rank correlation showed that Eberhart and Russell’s deviation from regression (S 2 di) was significantly and positively associated with s 2 , λi, δ 2 i and CV and negatively with r 2 . The parameters λi, s 2 , δ 2 i and CV also showed positive mutual association.

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A study conducted to determine the ecological status of vegetation under a Casuarina equisetifolia L. plantation revealed that the number of species types, density and biomass of the understorey were drastically reduced compared to an adjoining grassland area. In general, vegetation under Casuarina was characterised by the presence of a few dominants with a trend towards homogeneity. On the other hand, the vegetation in the grassland was heterogeneous, with conspicuous spatial pattern and, thus, more stable. Indices of richness (indicating numerical strength), evenness (representing spatial distribution), and diversity (combining both richness and evenness) also indicated a marked difference in the vegetation between the two sites. The Shannon index, indices of richness and evenness, and Hill. s diversity measures were greater in grassland areas than in Casuarina plantation, thereby signifying a richer, more diverse and even vegetation in the grassland. In contrast, the Simpson index of dominance which shows an inverse relation with diversity, was greater under the Casuarina plantation. The reasons for the restrained vegetation under Casuarina were explored in terms of allelopathic interference of various tree parts (fresh as well as fallen) as one of the major factor. The leaf leachates collected under the canopy of Casuarina trees in the plantation were found to have deleterious effect on the growth of Medicago sativa and Ageratum conyzoides and were rich in phenolics. The extracts prepared from different tree parts such as needles, female cones and litter adversely affected the growth and dry weight accumulation in M. sativa and A. conyzoides. An appreciable amount of water-soluble phenolics, known phytotoxins, was estimated in the fog leachates and different plant parts under use. It is concluded that phenolics released from the green needles and litter of the tree adversely affect the understorey vegetation.  

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A new wheat variety resistant to cereal cyst nematode (CCN), CCNRV 1 (Raj Molya Rodhak 1), was developed from two genetically diverse cultivars in a single cross (J 24/AUS 15854). This variety exhibited a higher level of productivity in both CCN-infested and normal soils, with increases in the grain and straw yields of 78.7% and 60.1%, respectively, over Raj 3077 in infested soils. It also gave 19.0% higher yield than local varieties under timely-sown irrigated conditions in normal soils. It possesses superior grain quality along with other desirable agronomic traits. Genetically it carries a dominant gene for CCN resistance. It is a robust and reliable wheat variety that offers a high degree of resistance against nematodes in warmer areas of Rajasthan. It was recommended for timely-sown, irrigated conditions in CCN-infested areas of Rajasthan by the State Seed Sub-Committee on Crop Standards, Notification and Release of Varieties in September 2002. It is envisaged that this variety will help to boost wheat production and alleviate the socio-economic problems of subsistent Indian farmers in CCN-infested areas.

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Thirty diverse elite Indian wheat genotypes varying in their yield performance and drought tolerance were evaluated to examine differences for some drought tolerance characters and to determine relationship between these characters. Genotypes differed in their response for grain yield, days to heading, excised-leaf water loss and relative water content under both conditions over years. Under irrigated conditions differences in the genotypes for water retention traits were not clear. The varieties HPW251, Hindi 62, HPW184, VL 892 and VL 907 showed a good combination of drought resistance, water retention and high grain yield, whereas C 306, VL 421 and NI 5439 had high grain yield only under drought stress conditions and showed better water retention in the leaves. These genotypes may be used for exploitation of drought tolerance in wheat breeding programmes. Drought response index (DRI) appeared to be an important trait as the genotypes having high DRI values also had high grain yield, high water retention and low score of drought susceptibility index (DSI) under drought stress.

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Maize cultivars (4 composites, 14 inbreds and 7 hybrids) cultivated in Punjab were characterized using a set of 70 Simple Sequence Repeat (SSR) markers with a total of 199 alleles. Out of these, 67 markers produced polymorphic profiles, 3 were monomorphic. Eight SSR primers detected eight unique alleles in three genotypes. These unique SSR alleles provide an opportunity for unambiguous differentiation of the respective genotypes. SSR profiles were analyzed by using computer softwares NTSYS-pc and DARwin 5.0. Both of them classified the genotypes in four distinct groups.

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Comparisons between androgenesis and maize-mediated haploid production efficiencies were made in six F1 genotypes each of winter × spring wheat and triticale × wheat crosses. The haploid status of the plantlets obtained was confirmed through cytological examination of the root tips. Much higher embryo formation (15.2%), haploid induction (8.7%) and doubled haploid production (8.3%) were obtained in the winter × spring wheat F1s through the wheat × maize system than by androgenesis (3.1%, 3.2 and 2.7%, respectively). Three of the triticale × wheat F1 genotypes failed to respond to androgenesis, while no haploids were recovered through the wheat × maize system in any of the six triticale × wheat F1s. Genotypic specificity, low callus induction and albinism reduced the efficiency of androgenesis both in winter × spring wheat and triticale × wheat hybrids. In all, the wheat × maize system proved to be better for winter × spring wheat hybrids and androgenesis for triticale × wheat hybrids.

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