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The leaf miner Coptodisca lucifluella and the carpophagous Rhagoletis completa, of American origin, are two non‐native walnut (Juglans spp.) pests in Italy. For the Friuli Venezia Giulia region (FVG) (N‐E Italy), C. lucifluella is not yet listed, while R. completa has been present for over 25 years. During 2015, samples of leaves and fruits were collected from 219 single old common walnut trees (Juglans regia) placed at different altitudes (0–1,073 m a.s.l.) in FVG to detect the distribution and abundance of both pests. Samples of leaf miner larvae and their parasitoids were subjected to mitochondrial DNA analysis for identification. C. lucifluella has been found in 55 out of 219 sites. The species has been identified by typical leaf symptoms and by its DNA barcode. This is the first report of the species for FVG. The leaf miner distribution was negatively correlated with altitude. The species has not been observed at sites over 600 m a.s.l. Larvae were parasitized by native parasitoids identified as belonging to the genus Chrysocharis by morphological features and by DNA barcode. R. completa has been found in 89 out of 165 sites on walnut trees with fruits. The infestation level was very high in lowland localities. At sites over 700 m a.s.l., no infestation was found. Both species are widespread in the region, and their occurrence is significantly affected by altitude. Data suggest that walnut trees could be cultivated in some mountain areas without the need to control R. completa with insecticides.

Few biochemical and molecular details are available on microspore growth and development. In this work, a nuclease was partially purified from diffusates of barley (Hordeum vulgare L.) microspores by using concanavalin-A as ligand. The chromatographic preparation contained a 34-kDa protein with nucleolytic activity; the enzyme (called BMN: barley microspore nuclease) was very stable at pH8.0 and temperatures below 50 degrees C. Activity was highest at pH 5.6 and increased almost exponentially with temperature until a breakpoint between activity and stability was reached at 70 degrees C. Although BMN was able to cleave RNA, the enzyme showed a remarkable preference for DNA, especially in the single-stranded form. The best homopolymeric substrates were poly(dA) and poly(A), whereas poly(dC), poly(G) and poly(I) were almost completely uncleaved. When incubated with intact nuclei, BMN caused a nucleosomal DNA ladder of approximately 200 bp. On the basis of DNA laddering, substrate specificity, Mg2+ -dependence and best performance at apoplastic pH, BMN can be referred to as a putative apoptotic nuclease involved in pollen development.

Experiments were designed to determine the seed content of protease inhibitors in different plants of a plot or at different nodes along the main stem. The inhibitory activity of the samples was measured in vitro using sodium benzoyl-DL-arginine-p-nitroanilide as chromogenic substrate and bovine trypsin as target enzyme. Six soya bean (Glycine max Merr) strains were used, three capable of synthesizing the Kunitz trypsin inhibitor (L62-364, Williams 82, and 594-1) and three lacking this particular function (L81-4590, L81-4871, and L83-4387). In all genotypes on trial, remarkable plant-to-plant variation was found, so that most strains had at least one part of the data distribution in common. Significant differences were also noted for antitryptic activities of seed samples collected at different positions on the main stem. Gradients interior to the plant varied according to the tested strain but those of Williams 82 and of its near isogenic line L81-4590 were very similar, indicating that the amount and type of variation depended on genotype and that changes in the inhibitory activity were attributable to variation in the synthesis of inhibitors other than Kunitz.

In modern, highly intensive agriculture, the control of insect pests is basically achieved with the appli- cation of chemical pesticides. Heavy reliance on this sole strategy is associated with several drawbacks, and the de- velopment of alternative or complementary methods to chemical control is desirable. In this work, three soybean genes (KTi3, C-II and PI-IV) coding for serine proteinase inhibitors were isolated by PCR and transferred to Agro- bacterium tumefaciens EHA 105, which in turn was used for transforming tobacco leaf and potato tuber discs. Bio- chemical assays confirmed that transgenic plants synthe- sized serine proteinase inhibitors; rates of expression varied among plants. The level of insect resistance (tested with Spodoptera littoralis Boisduval) was particularly high in tobacco, where many plants caused the death of all larvae. In potatoes, larval mortality was much less fre- quently achieved, but the results were still encouraging in that larval weight gain was reduced by 50% in the pres- ence of adequate amounts of inhibitor. When 8-day-old larvae were fed different KTi 3 -expressing tobacco plants, a highly significant (P