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Mealiness in "Forelle" pear is a textural disorder characterised by dry and soft texture deterioration, occurring mostly in fruit stored for less than the mandatory 12 weeks at-0.5°C. This study investigated the role of cell size in the development of mealiness in "Forelle" pear. Variations in cell sizes among fruit were incited by applying plant growth regulators: 2,4-D amine, prohexadione-Ca, gibberellin 4+7 and forchlorfenuron at different stages following bloom during the 2011 season. In 2012, hand thinning of fruit was done on blossom clusters, leaving fruit from the "king" blossom and one fruit from a smaller blossom. Cell size and other cell characteristics were examined on dried sections of the fruit cortex using scanning electron microscopy. Treatments that induced fruit with larger cells had higher mealiness percentage. Forchlorfenuron and its combination with gibberellin 4+7 produced fruit with significantly (P=0.038) higher mealiness percentage. 2,4-D amine had the least mealiness percentage compared to other treatments. Cell volume and cell diameter exhibited a positive linear relationship with mealiness percentage. Examination of histological differences between mealy and non-mealy fruit revealed differences in size of intercellular spaces with mealy fruit having larger spaces. The results from this study suggest that cell size and size of intercellular spaces are linked to the development of mealiness.

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Sweet wormwood (Artemisia annua L.) is a highly valued crop, native to China, whose active ingredient "artemisinin" and its derivatives: artemether and artesunate, are used to prepare anti-malaria drugs. In Zimbabwe, very little has been done on improving agronomic practices that can enhance the yield of this crop. As a result, herbal gardens in Zimbabwe producing this sweet aromatic herb are realizing low leaf biomass. The objective of this study was to determine the effects of varying nitrogen fertilizer levels on growth and yield of Artemisia annua. A randomized complete block design (RCBD) was used and replicated four times. The fertilizer treatments consisted of 0, 40 kg N/ha, 80 kg N/ha, 120 kg N/ha, 160 kg N/ha and were applied as a top dress four weeks after planting. Applying 80 kg N/ha, 120 kg N/ha or 160 kg N/ha resulted in the best performance of Artemisia annua with respect to the plant height, root dry weight, stem dry weight and leaf biomass. Low N level (40 kg N/ha) recorded significantly low means in plant height, root weight, stem weight and leaf biomass. The results suggest that 80 kg N/ha should be recommended for use by Artemisia annua farmers, since there was no significant different among the three higher fertilizer levels. However there is need for further research to determine different fertilizer use efficient to come up with accurate agronomic data package for Zimbabwean farmers.