Generation and analysis of expressed sequence tag sequences from a soft‐seeded pomegranate cDNA library

The cultivation of soft‐seeded pomegranate is an important direction in pomegranate breeding. To comprehensively understand the molecular mechanisms involved in the formation of soft‐seeded pomegranate (Punica granatum. var. Hongmanaozi), we established an expressed sequence tag (EST) resource. Two thousand valid sequences were generated, from which 907 unigenes were obtained after initial assembly using the clustalx program. Among these unigenes, 51 showed no similarity to any protein in the public databases, 433 matched with proteins of unknown function, and 423 matched with proteins of known or putative functions. The 423 unigenes were further classified into 13 categories. Among these categories, protein synthesis, cell structure, protein destination and storage, secondary metabolism, signal transduction and transporters accounted for 8%, 8%, 4%, 7%, 6% and 17%, respectively. We also successfully developed 10 highly polymorphic expressed sequence tag‐simple sequence repeat (EST‐SSR) markers for pomegranate. The results provide a new tool for future activities in pomegranate breeding.     

Evaluation of Schizophyllum commune Fr. potential for biodegradation of lignin: A light microscopic analysis

Lignin biodegradation potential of Schizophyllum commune Fr. is studied by using sound wood blocks of Ailanthus excelsa, Azadirachta indica, Tectona grandis, Eucalyptus sp. and Leucaena leucocephala. Initially, in vitro wood decay test showed minor weight loss, but it became rapid after one month. After 120 days of incubation, weight loss was minimum in T. grandis (24.05%) whereas it was maximum in A. excelsa (34.44%). Treated test blocks were characterised by enlargement of pits on ray cell wall, formation of additional boreholes in rays, separation of fibres and cell wall thinning and formation of ‘U’-shape notches. Fungal hyphae moved through the xylem cell lumen, and intercellular spaces formed in response to separation of fibres. Hyphae traverse in adjacent cell through the cell wall pits or by making additional boreholes. In all the species studied, xylem fibres and parenchyma (axial and ray) cells were more susceptible while vessels were resistant to fungal attack. In advanced stage of decay, fibres and axial parenchyma lost their rigidity while vessel walls showed uneven thinning. In the tension wood, G-fibres remained unaffected initially but loosening and separation of gelatinous layer facilitated fungal action and showed similar pattern of cell wall deterioration. Among the wood of different species studied, Tectona was more resistant whereas Ailanthus was more susceptible to fungal attack.     

Trophic-level modelling of the coastal waters of the northern Bay of Bengal,West Bengal,India

An ecosystem model was constructed for the northern Bay of Bengal (nBoB) using Ecopath (version 6.4.4). The model covered an area of 18,500 km². There were 32 functional groups in the model including the non-living group, detritus. Trophic levels (TLs) for individual groups ranged from 1.0 to 4.22. Ecotrophic efficiency for most of the small pelagic fishes was found to be greater than 0.7. For hilsa it was 0.853, indicating high exploitation of this fish within the system. The nBoB was estimated to be a low ascendancy area (~?19.2%) with a system overhead of 80.8%, which indicates system stability and a certain maturity. The total system throughput and the total primary production/total respiration estimated for the study area indicate that nBoB is a maturing ecosystem. The mean TL of the catch for the study area was 3.115. The results indicate that the nBoB system is still in a developing stage. The low mean TL of the catch indicates fishing practices targeting fish of lower TLs in the system. In the long run, this may cause fishing down the food web, which will eventually lead to declining catches. These results indicate that present fishing practices are unsustainable for the nBoB ecosystem.     

Anatomical changes in the cell-wall structure of Leucaena leucocephala (Lam.) de Wit as caused by the decay fungi Trametes versicolor and Trametes hirsuta

The structural changes in the cell wall and delignification pattern caused by Trametes versicolor and Trametes hirsuta in the sap wood of Leucaena leucocephala were examined by light and confocal laser scanning microscopy. The in vitro decay test was conducted for 12 weeks. Both species of Trametes used in this study caused anatomical characteristics specific to simultaneous white rot. Formation of boreholes, erosion troughs, erosion channels with U-shaped notches in tangential sections and thinning of cell walls were evident in the wood inoculated with each of the fungal species. Cell separation due to removal of middle lamellae occurred at the early stages of infection (30 d) with T. versicolor. In contrast, middle lamellae remained intact in wood inoculated with T. hirsuta and showed cell separation due to degradation of the outer layer of the secondary wall and degradation of the middle lamellae observed only in severely decayed wood at late stages. Confocal microscopy revealed the delignification pattern particularly from cell corners and vessel walls at an advanced stage of decay, indicating strong ligninolytic activity of both species in the sapwood of L. leucocephala.     

The Delignification Pattern of Ailanthus excelsa Wood by Inonotus hispidus (Bull.: Fr.) P. Karst.

In vitro laboratory decay tests on Ailanthus excelsa Roxb. wood revealed that I. hispidus exhibits a combination of both white-rot and soft-rot patterns of wood decay. Early stages of wood decay showed dissolution of the middle lamella as well as defibration and localized delignification of fiber walls; vessels, axial, and ray parenchyma remained unaltered. Delignification commenced from the middle lamellae at the cell corners without any marked effect on the primary and secondary wall layers. In later stages of growth, the species produces typical soft-rot decay pattern by forming erosion channels through the S₂ layers of fiber walls, transverse bore holes in the cell walls, and erosion channels alongside/following the orientation of cellulose microfibrils. The rays showed signs of cell wall alterations only after the extensive damage to the fiber walls. After 120 days of incubation, the vessels also showed localized delignification, the erosion of pits, and separation from associated xylem elements. The extensive weight losses under natural and in vitro decayed wood as well as the very soft nature of severely degraded wood indicate that I. hispidus alters wood strength and stiffness.     

观赏植物生物技术研究进展(英文)

观赏园艺产业的发展,需要观赏植物品种的不断创新,包括品质的提高和种类的多样化。而品种的创新一方面依赖对植物生长发育过程的理解,另一方面需要新的生物技术的创新与应用。伴随着生命科学的快速发展,新的生物技术也不断涌现,为观赏植物新品种的培育提供了新的方法与手段。本文从细胞工程,分子标记及基因工程三方面,论述了现代生物技术在观赏植物中的应用。其中重点介绍了基因工程在观赏植物性状改良方面的应用,包括形态改良,生物及非生物胁迫抗性的提高,以及采后寿命的延长。最后,对一些可能应用于观赏植物并促进其发展的生物技术进行了展望。     

More from Less: Policy Options and Farmer Choice under Water Scarcity

In much of the world, fresh water isscarce and getting scarcer. Growing populations, increasing industrialisation, and environmentalconcerns have all put pressure on the water consumedby agriculture. This paper addresses the economicconsequences of a permanent reduction in canal waterfor irrigation. Using detailed cost-of-cultivationdata from the Gediz Basin, Turkey, the key questionsare: How can farmers best respond to reduced surfacewater supplies? How can the canal managementauthorities best distribute this limited water? And,can the demand for water be reduced through input andoutput price policy? These questions are answered withscenario comparisons under several water availability,crop pattern, price and investment assumptions, forthe short and medium time horizons. Keeping productivity high and water use low requirescoordination between farmers and the water managementauthorities. The analysis shows that, in this region,farmers should keep all their land irrigated at loweryield levels, rather than reduce their cropped areas.The canal managers should opt for a short irrigationseason, rather than an extended season with long dryintervals. Sensitivity analysis on a range of pricesindicates that crop, rather than water prices, affectthe efficiency of water use. The scenarios areevaluated using AGWAT, a spreadsheet-based farm-budgetprogram which is simple and widely applicable. Therange of policy choices considered establishes aframework of analysis for other, potentiallywater-short basins, beyond the Gediz or Turkey.     

Role of lunar phases,rainfall, and wind in predicting Hilsa shad (Tenualosa ilisha) catch in the northern Bay of Bengal

Hilsa (Tenualosa ilisha) is an important commercial fish in India. This study investigates relationships among Hilsa catch per unit effort (CPUE) and the corresponding lunar phase, rainfall variability, wind vector, and month in the northern Bay of Bengal. Hilsa catch during the monsoon season of three consecutive years (2013–2015) was analyzed by using a Generalized Least Square model with lunar phase and monsoon months (June–September) as categorical variables and wind direction as circular variable. Significantly higher Hilsa catch was observed during the waning crescent and waxing gibbous lunar phases and during easterly winds. There was no significant effect of wind velocity. Daily rainfall was significantly correlated with Hilsa migration toward the estuary. Among the four monsoon months, September exhibited the most positive significant correlation with the Hilsa CPUE. Model predicted CPUE underestimated the actual CPUE in 2016 by 20%.     

Histological changes in the cell wall structure during wood decay by Trametes hirsuta and Trametes versicolor in neem (Azadirachta Indica A. Juss)

ABSTRACT

Structural alterations in the wood cell walls of neem inoculated with by Trametes hirsuta and T. versicolor were studied by microscopic methods. In vitro decayed wood showed extensive weight loss of test blocks (26.7 and 41.38% by T. versicolor and T. hirsuta, respectively) at the end of 3 months. Selective delignification in the initial phase followed by simultaneous removal of lignin was evident in test blocks inoculated with both the species. The separation of middle lamellae and patches of cellulosic polysaccharides stained blue with Astra blue in the delignified region of the fiber wall during early stages indicates selective mode of decay. In contrast, the occurrence of erosion troughs with characteristic U-notch in tangential sections is a characteristic feature of simultaneous rot that was apparent after 3 months of incubation. The decay pattern occurred concomitantly in all the xylem elements irrespective of general resistance pattern shown by vessel and axial parenchyma cells. At an advance stage, both species of Trametes showed formation of erosion channels along the microfibrils angle of cellulose which is considered as characteristics of soft rot decay type. The sharing of white rot and soft rot decay pattern by both the fungi suggest a phylogenetic link between both groups of fungi.