Several instances of nutritent deficiency of grapevines occurred in vineyards of Osaka prefecture were collected for investigation.
The information obtained from these instances are found to be useful for nutritional diagnosis of plant and soil test.
The results were as follows.
1) Magnesium deficiency: Under greenhouse conditions leaf Mg contents of ‘Delaware’ and ‘Kyoho’ grapes showing Mg deficiency symptoms were less than 0.09% and 0.12%, respectively. Exchangeable Mg content in the vineyard soil of ‘Delaware’ was less than 13 mg/100 g. Such a low level of exchangeable Mg was obviously insufficient for healthy growth of ‘Dela-ware’ grape. On the contrary, Mg deficiency symptom was observed on the leaves of ‘Kyoho’ grapes growing in the soil having exchangeable Mg as high as 50 mg.
2) When Mn concentration in the leaves was less than 21 ppm, the interveinal tissue turned light green and the berries had poor coloration.
The pH (H₂O) of such a soil was nearly 7.0 and exchangeable Mn was less than 3 ppm. Mn deficiency symptom was markedly decreased by foliar application of 0.4% MnSO₄ solution. The effect was greater when applied after anthesis rather than before it.
3) Boron deficiency : When leaf B concentration was 7-13 ppm, boron deficiency symptom was found on younger leaves and inside of berries.

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Several instances of nutrient deficiency symptoms observed in citrus trees growing in some orchards in Osaka prefecture were collected for investigation.
The information obtained from these instances are found to be useful for nutritional diagnosis of plant and soil test.
The results were as follows.
1) Magnesium deficiency: Magnesium deficiency symptom appeared in the old leaves lowing Mg concentration less than 0.13%. The content of exchangeable Mg in such a soil was less than 21 mg/100g.
2) Iron deficiency: Interveinal chlorosis was observed in leaves of low Fe concentration. The trees having such leaves were grown in the soil where pH and exchangeable Fe were low, but exchangeable Mn and available P₂O₅ were very high.
3) Manganese deficiency : Mn deficiency symptom appeared in the leaves having Mn concentration less than 16 ppm. This deficiency was markedly decreased by foliar application of 0.3% MnSO₄ solution.
In such a soil pH (H₂O) was higher than 6, CaO was generally high, but exchangeable Mn was lower than 3 ppm.
4) Zinc deficiency: Zn deficiency symptom appeared in the leaves having Zn concentration as low as 16 ppm, and their young leaves turned light green, or yellow mottling appeared between the veins. The pH (H₂O) of such a soil was higher than 7.3, and the content of exchangeable Zn and 2 N MgCl₂-extractable Zn were markedly low.
5) Boron deficiency; Boron deficiency symptoms on leaves or inside of fruits occurred when B concentration in the leaves lowered in a range 9-16 ppm.

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Newly hatched larvae of Bombyx mori displayed positive phototactic response, but the response was rapidly suppressed after the larvae were fed on mulberry leaves or exposed to the odour of the leaves (Fig. 2) . The suppression of phototaxis continued subsequently in the absence of mulberry leaves, but the response was recovered gradually. This suppression was satisfied by placing the larvae in the presence of methanol extracts prepared from mulberry leaves. It was demonstrated by a paper chromatography that the suppressive principle was distinct from attractants (Fig. 5) . From electrophysiological study it was shown that peripheral photoreceptive organ was not involved in the suppression of phototaxis by mulberry leaves (Fig. 3) . Electric shock treatment caused a recovery of phototaxis immediately, and this strongly suggested an involvement of central nervous system in the suppression (Fig. 4) . Adaptive significance of the loss of phototaxis was presumed to be an arrest of the silk-worm larvae on the host plant.
When the larvae were fed on artificial diet which contained no mulberry leaves, their responses were not affected at least by 24 hr-feeding (Table 1) . However, the phototactic response was decreased gradually with larval growth (Fig. 6) . This observation showed that physiological changes caused by the growth affected the phototaxis of the silkworm larvae.

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An attempt was made using a nuclear magnetic resonance (NMR) computed tomography (CT) system to measure spatial distributions of soil water and main roots of broad bean and Japanese radish plants growing in the soil without destroying the plants and the soil environment.

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