The time for half of the total oxidizable carbon to be converted into CO 2 and other gaseous products (tl/2) was studied for five tree species used in agroforestry. The study was conducted in a perfusion system with continuous aeration, and moisture content maintained at field capacity. This method was found to be suitable for studies of the initial stages of tree foliage decomposition. The overall rate was in the decreasing order: Leucaena > Calliandra > Gliricidia > Prosopis > Cassia. Decomposition started rapidly and then decreased rapidly for 2 to 3 weeks followed by a gradual decrease which continued for the remainder of the time.The time for 50 per cent of total oxidizable carbon to decompose was about 19 days for Leucaena, 30 days for Calliandra and Gliricidia, while Prosopis and Cassia took more than 30 days. Leucaena released the largest quantity of total N into the perfusing solution while Cassia gave the lowest amount.

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The passion fruit was introduced to Kenya through Europe in the 1920s, and only gained significant economic importance in the 1990s. Several species of the genus Passiflora present potential superior characteristics for genetic breeding of the passion fruit germplasm. Quantitative morpho-agronomic traits are important in passion fruit breeding since they allow for discrimination of varieties for important parameters that are useful in selection of fruit for market. The present study aimed at evaluating existing phenotypic variation between the Purple and Brazil varieties as well as their hybrids, developed by the Kenya Agricultural and Livestock Research Organization (KALRO). Seven quantitative morpho-agronomic traits were targeted with replication per plant and variety. Principal component technique and cluster analysis statistical tools of Minitab 17.0 software were used to discriminate the accessions under study based on the morpho-agronomic traits. Both the dendrogram and scatter plot clustered accessions based on their respective varieties, an indication of phenotypic relatedness within varieties. The results of this study will supplement the current body of knowledge on Kenyan passion fruit breeding.

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Purpose: This research paper focused on the impact of Cuscuta campestris on vegetative cover and plant biodiversity in Homa-Bay County. The specific objective was to investigate the impact on plant growth and development with indicator as photosynthetic capacity of preferred host plants and chlorophyll content and leaf weight as the parameters. Methodology: The study was conducted in hot-spot areas of invasion, Rachuonyo North, Homa Bay town and Suba North using Completely Randomized Experimental Block Design. The data was collected through field observation and laboratory analysis. The study used descriptive and correlation data analysis procedures to show the impact on photosynthetic capacity, ANOVA to determine statistical significant difference among the obtained results for each parameter of the infected and uninfected samples. Variance analysis were conducted using SPSS 20 (IBM Corp. Armonk, NY, USA) and differences between means tested by ANOVA. Values of P ≤ 0.05 were considered significantly different. Findings: The results showed that the invasion was more intense in Theveta peruvinia and Euphorbia tirucalli species. Mean leaf amounts of chlorophyll were observed to decline with chlorophyll a from 3.97 to 1.59 mg/g and chlorophyll b from 2.65 to 1.18 mg/g and total chlorophyll value from 6.62 to 2.76 mg/g on infection resulting to reduced photosynthetic efficiency and low organic material formation. Leaf wet and dry weight significantly decreased in both infected varieties. The mean wet weight of 17.61g in infected was significantly different, F (1, 4) = 235.74, p< .05, from the mean wet weight of 24.23g in the uninfected Yellow Oleander while the mean dry weight of 5.55g in infected was significantly different, F (1, 4) = 159.72, p< .05, from mean dry weight of 7.87g in uninfected Yellow Oleander. Similarly, significant difference, F (1, 4) = 714.64, p< .05, was observed in Calliandra calothyrsus variety. These demonstrated how C. campestris is detrimental causing ecological impacts with direct effects on plant biodiversity by reducing growth and development of infected host plant and even leading to death. Unique Contributions to Theory, Practice and Policy: The paper recommends intense sensitization of the community on the impacts of dodder from the findings for an enhanced understanding and need for management and control. The findings to be disseminated through workshops involving farmers, NGOs and community based organisations, academic conferences and publications to help create awareness on the impacts and mobilize the entire public on management and possible total eradication. Further research to investigate on nutrients of attraction in the preferred host plants with an aim of permanent solution for total eradication in order to restore the vegetative cover and plant biodiversity.