The cosmotropical urban mosquito Culex quinquefasciatus Say (Diptera: Culicidae) uses chemical cues to locate suitable water pools for oviposition. Although gravid females are innately attracted to or repelled by certain compounds, this study found that an individual mosquito's preferences for these odours could be altered greatly by prior experience. Mosquitoes reared in water containing skatole, at a level normally repellent to ovipositing females, preferred to oviposit in water containing that compound rather than in water with an otherwise attractive odour compound (P-cresol). This behaviour occurred regardless of whether mosquitoes were tested individually or in groups of up to 50 per cage. The F1 progeny of conditioned mosquitoes did not exhibit the parental preference, but were as susceptible to conditioning as their parents. Moreover, rearing mosquitoes in infusions of hay or animal (guinea-pig) faeces produced a similar although less dramatic change, such that the innate propensity for hay infusion could be cancelled by rearing in guinea-pig faeces infusion. The results demonstrated a change in odour preference by Cx. quinquefasciatus following exposure to the odour during development or pupal eclosion, suggesting that some form of larval conditioning or early adult imprinting occurred. Precisely when that conditioning occurred remains to be determined.

A cytological study of the megagametophyte in Prunus avium was undertaken to determine to what extent delayed development, cytological irregularities, or degeneration might account for failure of this fruit to set commercial crops. In 1957, under high temperatures, the proportion of embryo sacs with functional egg cells decreased rapidly following anthesis. In 1958, under low temperatures, the maximum proportion of functional embryo sacs at any one time was much lower than in 1957, and the proportion of embryo sacs with functional egg cells began to decrease within 2 days of anthesis. At anthesis in both years sufficient functional embryo sacs were present to allow a commercial set of fruit. The importance of cross-pollination immediately at anthesis is emphasized. The conclusions are supported by studies of pistils hand-pollinated at intervals after anthesis.

Strawberries from six cultivars, 'Mrak', 'Ranier', 'Redcrest', 'Selva', 'Sumas' and 'Totem', were compared for sensory attributes, chemical properties and 25 selected volatile compounds. 'Redcrest' strawberries had the most intense sourness, lowest pH, high titratable acidity and least overall fruit quality rating. Two-dimensional partitioning (TDP) revealed that overall quality ratings of the strawberries from all cultivars were dependent primarily on odor and sweetness. Cultivars differed in all orthogonal variates except odor. While judges could not detect odor differences, volatiles were greatest in 'Mrak' and 'Selva' and least in 'Ranier' and 'Redcrest'. Canonical variate analysis (CVA) based on 25 selected volatile compounds was used to classify cultivars according to the region in which they were bred.

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