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The article discusses a study which was carried out to identify the causal agent of unusual symptoms associated with lily plants. It included greenhouse work and laboratory testing. The greenhouse results showed that lily bulbs collected from diseased-like plants produced shoots with an unusual trend of plant growth and development when compared to healthy plants.

We describe for the first time the full 3D atomic structure of room-temperature α-La2Mo2O9. The material, despite its simple chemical formula, has a remarkable 312 crystallographically unique atoms and is thus one of the most complex oxide structures reported to date. Despite this complexity, the structural results offer significant insight into the O^2- migration pathway in the anion conducting high-temperature form, β-La2Mo2O9. The material contains a mixture of 4, 5, and 6 coordinated Mo sites, suggesting that variable Mo coordination number is a key factor in providing a low-energy O^2- conduction pathway. We provide quantitative analysis showing that the positions in the ordered array of 216 oxygen sites of α-La2Mo2O9 are directly related to the average sites occupied in β-La2Mo2O9, providing compelling evidence that the high-temperature conducting form of the material has a time-averaged version of the low-temperature structure.

Individuals of the cowpea aphid, Aphis craccivora Koch; the melon aphid, A. gossypii Glover; the spirea aphid, A. spiraecola Patch; and the green peach aphid, Myzus persicae (Sulzer), were allowed to probe on leaves of bean, crotalaria, and citrus. The probing response of all 4 aphid species to the various leaves was similar. More than 65% of probes on upper or lower surfaces of mature citrus leaves were less than 15 seconds in duration, whereas, less than 35% of probes were of that duration on leaves of other hosts. Virus transmission from bean and crotalaria leaves was considerably lower from probes under 15 seconds in duration than from probes exceeding 15 seconds, suggesting that more than 15 seconds are usually necessary before aphid stylets are able to reach virus-containing regions in the epidermis. Frozen sections of leaves cut with a microtome failed to reveal any obvious anatomical differences that would account for the brevity of aphid probes on mature citrus leaves. We suggest that, upon maturity, the cuticle and/or cell walls of citrus leaves develop a condition that renders them repellent to aphids, and that this condition accounts for the brevity of probes by aphids placed on these leaves.