ABSTRACT
Brown blotch disease (BBD) caused by Pseudomonas tolaasii is one of the most devastating diseases of Pleurotus spp. worldwide. Breeding for resistant strains is the most effective method for controlling BBD. To identify resistant germplasm for BBD management, 97 strains comprising 21 P. cf. floridanus, 20 P. ostreatus, and 56 P. pulmonarius were screened by two different methods; namely, inoculation of the pathogen on the mushroom pileus (IMP) and on the spawned substrate (IMSS) under controlled conditions. Out of the 97 strains screened, 22 P. pulmonarius, and four P. cf. floridanus were moderately resistant to BBD using the IMP method. Eleven P. pulmonarius, six P. cf. florida, and one P. ostreatus strains were highly resistant to BBD using the IMSS method. All of the 97 strains showed varying degrees of susceptibility using the IMP method, but eight strains were completely resistant using the IMSS method. Combining these two methods, five strains were highly resistant (four P. pulmonarius and one P. cf. floridanus) and 11 were moderately resistant (eight P. pulmonarius and three P. cf. floridanus). The resistance sources to P. tolaasii identified in P. pulmonarius and P. cf. floridanus could be used for further breeding of Pleurotus spp.
ABSTRACT
Agaricus bisporus is well known for its nutraceutical properties. To meet consumer market demand, there is an urgent need for new strains with disease resistance and a diverse nutrient profile for commercial cultivation. Wild germplasm resources provide a good source for the breeding of new strains for this purpose. In this study, we evaluated the physical, chemical, and structural properties of wild domesticated (CCMJ1351) and major commercially cultivated strains (CCMJ1013, CCMJ1028, and CCMJ1343) of A. bisporus from China. The results showed significant differences among the strains for all parameters measured. In terms of morphological characteristics, CCMJ1351 possessed the highest stipe thickness, fruiting body individual weight, cohesiveness, and springiness; CCMJ1013 demonstrated maximum pileus diameter and thickness; CCMJ1028 exhibited the highest textural hardness and color characteristics; and strain CCMJ1343 had the highest yield. CCMJ1351 ranked top among all the strains for proximate composition, rheological profile, and structural and mechanical properties, containing 21.93% crude protein and the highest dry matter, crude fat, and fiber contents. However, the bioactive chemical constituents present in the four strains were very similar, especially ß-(1â3)-glucan, according to Fourier transform infrared spectroscopy analysis, while some minimal peaks varied among the different strains. Therefore, in combination with previously identified high disease-resistance traits, the wild domesticated strain CCMJ1351 constitutes a good candidate for further exploitation in breeding programs and is suitable for fresh consumption as well as incorporation into various food products.
