Photosporogenesis of Coprinus congregatus: Correlations between the physiological age of lamellae and the development of their potential for renewed fruiting

When the hymenial lamellae of Coprinus congregatus Bull ex Fr. are used as implants, their potential for renewed fruiting varies according to the photocontrolled meiosis and the consecutive sporogenesis. In the case of young lamellae, whose basidia are still at the dikaryon stage, one can observe immediate start of mycelial growth all around the lamellae and production of the first mature sporophores directly on the lamellae (direct fruiting). Simultaneously, meiosis does not occur in hymenial cells. Conversely, in the case of implantation of the oldest lamellae, whose basidia are characterized by meiotic nuclei beyond prophase 1 and rather near telophase 2 (tetranucleate stage), vegetative growth starts slowly and the first mature sporophores are not produced on the lamellae but on the surrounding vegetative mycelium (indirect fruiting). When the lamellae are isolated from photoindifferent primordia – for instance, 12 h before maturity – sporogenesis in hymenial cells proceeds normally until autolysis of the isolated lamellae. Such isolated lamellae no longer show direct fruiting where the first flush is concerned.     

Extracellular enzyme activities in six Lentinula edodes strains during cultivation in wheat straw

Lentinula edodes (Berk.) Pegler is found in nature on dead broadleaf trees, but it is commercially produced on different substrates. The question of adaptation to different lignocellulosic substrates was addressed by measuring enzyme activities produced by six strains that were cultivated on wheat straw and that were able to produce sporophores. Despite quantitative variations, each strain of L. edodes had similar patterns of enzyme secretion into the wheat straw log matrix. Two peaks of carbohydrase activities were observed, the first relating to the early mycelial growth during the first days after spawning and the second during sporophore extension. Laccase activity in the early stage of colonization was related to the degradation of soluble phenolic compounds present in wheat straw. Manganese peroxidase activity was associated with mycelia th. The strains with the earlier production and higher yield were able to hydrolyse and utilize straw cell wall components soon aft er inoculation, and developed high metabolic activities.     

Studies on antagonistic marine actinomycetes from the Bay of Bengal

Screening of 26 marine sediment samples near 9 islands of the Andaman Coast of the Bay of Bengal resulted in the isolation of 88 isolates of actinomycetes. On the basis of sporophore morphology and structure of the spore chain, 64 isolates were assigned to the genus Streptomyces, 8 isolates to the genus Micromonospora, 5 to the genus Nocardia, 7 to the genus Streptoverticilium and 4 to the genus Saccharopolyspora. Among 64 Streptomyces spp., 44 isolates showed antibacterial activity and 17 isolates showed antifungal activity. Three isolates showed very promising antagonistic activities against multi-drug resistant pathogens.     

全白绒泡菌部分生活史图解

为深入了解全白绒泡菌生活史过程,对其孢子萌发、黏变形体和游动胞的相互转变、游动胞在5 s内的运动轨迹及原质团形成孢囊的过程进行了显微镜下观察和拍照,并对部分生活史阶段进行了时间测定,提出黏菌孢子萌发的第三种方式,提供了清晰的全白绒泡菌部分生活史的图片。     

Ganoderma – a basal stem rot disease of coconut palm in south Asia and Asia pacific regions

Basal stem rot (BSR) caused by the species of Ganoderma is one of the most devastating diseases of numerous perennial, coniferous and palmaceous hosts. In forest systems, Ganoderma has an ecological role in the breakdown or delignification of woody plants. Symptoms of BSR disease can take several years to develop, and the presence of the pathogen (such as indicated by fruiting bodies) is often only visible when the fungus is well established and more than half of the bole tissue has been decayed, leaving no chance for the grower to cure the infected palms. Soils with poor drainage and water stagnation during rainy seasons were found to favour the disease. A limiting factor in controlling the BSR disease is the lack of reliable diagnostic method(s) for early diagnosis. Amendment of calcium nitrate in soil is one of the methods for the management of Ganoderma disease in palms. A combination of biological and systemic fungicides along with good cultural practices will effectively control the BSR disease in palms.     

Cultivation studies on wild and hybrid strains of Pleurotus tuberregium (Fr.) Sing. on wheat straw substrate

Wild of strains Pleurotus tuberregium from Nigeria and the Australasian-Pacific regions and selected hybrids were studied to determine their growth and sclerotia production capacity on wheat straw substrate. Although the Australasian-Pacific strains showed faster growth rates, the wild strains from Nigeria performed better than the Australasian-Pacific strains in sclerotia yield. Under similar conditions, some hybrids had sclerotial yields that were higher than any wild strain. Our study showed the possibilities of using selected strains and the low cost methods adopted in this experiment, for the cultivation of sclerotia of P. tuberregium.     

Recycling spent larval food of Corcyra cephalonica Stainton for preparing spawn and sporophore of Pleurotus sajor-caju (Fr.) Singer

Large scale production of the rice moth, Corcyra cephalonica Stainton in pearl millet grain medium leads to a huge accumulation of spent larval medium in commercial insectaries. We attempted bioconversion of spent larval medium of C. cephalonica (CLM) for cultivation of the mushroom Pleurotus sajor-caju (Fr.) Singer, to increase the usage of these residues. Maximum efficiency limits of CLM for spawn run, sporophore cropping and as bed substrate were assessed with varying combinations of sorghum and rice straw. Sorghum grains and rice straw were the best substrates for spawn run and sporophore yield respectively. Having been crushed, macerated, heated and sterilized, CLM could also become a suitable substrate along with sorghum or rice straw. Sorghum and CLM at 16.7% + 83.3% and 33.3% + 66.7% combinations were very effective in supporting mycelial growth and quicker colonization of fungus, and mother spawn yield. The spawn that was obtained from these combinations yielded higher sporophore as well. The fungus did not rapidly colonize on other combinations (50% + 50%, 66.7% + 33.3% and 83.3% + 16.7%), and was completely unable to grow on CLM 100%. Combination of rice straw and CLM at 75% + 25% and 50% + 50% as bed substrate contributed higher sporophore yield. Analysis of the substrates indicated variation in their chemical and mineral composition, but they were good sources of N, P and Ca. The prospects of exploring CLM for the mushroom cultivation are discussed.