Fungi Causing Post-Harvest Spoilage Carica papaya Linn Fruits of Two Selected Markets in Kano State, Nigeria

This study was carried out for four month (September, 2015 to December, 2015) to find the fungal species associated with post-harvest spoilage of pawpaw fruits sales at Na’ibawa and Wudil Markets all in Kano State. A total of five strains of fungi were isolated and identified as Aspergillus niger, Aspergillus flavuus, Rhizophus stolonifer, Yeast, and Fusarium. Pathogenicity test of each fungal isolate showed that all fungi were capable of causing rotting of the fruit and most severe rotting was caused by Aspergillus niger and Yeast with 8(29.63%) Respectively at Na’ibawa market and 10(34.48%) and 9(31.03%) at Wudil market followed by Rhizophus with 7(25.93%) and 5 (17.25%) while Aspergillus flavus and Fusarium produced the least rotting of the fruit. The difference in the fungal spoilage of Carica papaya between the two market areas Na’ibawa and Wudil markets was statistically significant (p≥0.05). From the result of this study, it is clearly indicated that the spoilage of pawpaw fruits in the two markets was due to fungal attack.

Comparative study of the effect of salt stress, Alternaria alternata attack or combined stress on the Cakile maritima growth and physiological performance

Cakile maritima is a halophytic plant model that is well known by its ability to tolerate high salt concentrations. Salinity was reported to improve the tolerance of halophytes to several abiotic stresses; however, the involvement of salt in the tolerance to biotic stress is still scant. In the present work, the effect of salt on C. maritima responses towards the pathogenic Alternaria alternata was investigated. For that, C. maritima seeds were germinated for four weeks. Plants were then divided into four groups: i) Plants irrigated with salt (200mM NaCl); ii) Plants infested by fungus; iii) Plants irrigated with salt and infested by fungus and finally control plants (0mM NaCl, without inoculation). Our results showed that upon salt stress or fungal attack, plants reduced biomass production, hydration status and photosynthetic performance which were associated with a decrease in the gas exchange and chlorophyll fluorescence parameters, with a more pronounced effect upon fungal attack. However, under combined stress, a significant increase of these parameters was noticed, with a level close to that of control. Concerning nutrient contents, K, Zn, Fe, Cu and Mg decreased in the C. maritima leaves exposed to both stresses applied individually. In contrast, all these nutrients were increased in plants grown under combined stress. Taken together, we can conclude that plants grown under combined stresses had better growth rate and physiological performance compared to all other treated plants, and that salt may be the key in improving the C. maritima ability to tolerate fungal attack.

CMSERK GENE IS EXPRESSED IN RESPONSE TO THE ATTACK OF PATHOGEN FUNGI COLLETOTRICHUM ACUTATUM AND BOTRYTIS CINEREA

The genus Cattleya groups orchids originate in tropical zones of South and Central America. One of the most representative species of ornamental importance is Cattleya maxima Lindl. In this study the fungal pathogens Colletotrichum acutatum and Botrytis cinerea were isolated and their pathogenicity was determined by in vitro inoculation of Cattleya maxima. Pathogenicity tests resulted positive for infection with C. acutatum after seven days of inoculation while as for B. cinerea the symptoms of infection appeared after two days. Quantitative PCR revealed that CmSERK gene is more expressed in tissue under fungal attack. These results suggest that CmSERK gene plays an important role in the activation of defense-related responses.

Innovation in Wood Preservation

The wood preservation industry has depended on toxicity as a mechanism of effectiveness against decay fungi to extend the life of wood used in adverse conditions. An alternative to toxicity, however, is to study and understand the mechanism of fungal attack and stop it before it can start. Knowing that fungi need moisture for colonization, a new approach to wood preservation is to lower the cell wall moisture content below that needed for fungal attack. Acetylation chemistry is known to reduce the moisture content in the cell wall, and it was used to study moisture levels in the bulk cell wall and in the isolated cell wall polymers. Resistance to brown-rot was determined using a 12-week soil block test with Gloeophyllum trabeum. Weight loss was measured and an analysis of what was lost was determined.

Alerting Spoilage of Food in Refrigerator

The era of smart homes wouldn’t be complete without intelligent refrigerators. Thus we have proposed an idea for detecting the food kept in the refrigerator and alerting the user on their spoilage which involves all the processes of ML and IoT. In places where large stocks of food are stored, manual maintenance is very hard and also when they are transported to long distant places from the cultivated lands to the end-users, they get spoiled due to lack of governance. The existing systems have provided a solution forthis and we decided to give thisfacility forthe working women who have very little time to do their household. This system helps in preventing other items in the refrigerator from the fungal attack caused by the affected ones. The solutions provided by the existing systems recommend sensors to detect the food items. Each food item might need a different sensor and hence this might lead to a lot of hardware components to be added to the refrigerator. Thus our system uses ML prediction methods like image processing. Finally, the notification of the spoiled food is intimated to the user by displaying the message in the refrigerator door.

Effect of Multiple Leaching Cycles on Decay Resistance of Micronized Copper Azole–Treated Southern Pine Sapwood

Copper remains one of the key biocides for protecting timber in soil contact. Historically, copper-based preservatives relied on solubilized copper. Over the past decade, micronized copper systems have largely replaced soluble copper systems in this application. While micronized copper chemistries have been shown to perform well over time with reduced copper leaching compared to solubilized copper, data are lacking on the effects of repeated leaching cycles on resistance of the timber to fungal attack. The potential effects of repeated leaching cycles of micronized copper azole–treated southern pine (Pinus spp.) blocks on both copper losses and resistance to fungal attack were explored over 20 leaching cycles using Gloeophyllum trabeum and Rhodonia placenta as test fungi. Copper losses during leaching were elevated for the first two cycles and steadily declined with additional cycling. There were no noticeable differences in fungal-associated weight losses in blocks exposed to G. trabeum. There was only a slight increase in average block weight losses with R. placenta, although blocks exposed to this fungus experienced higher weight losses with increased leaching cycles. The results suggest that repeated leaching exposures may produce some localized increases in susceptibility to fungal attack, but the overall effects were minor.