• Journal of Biosystems Engineering
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• v.25 no.6
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• pp.511-516
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• 2000

The strength of the connecting joint of boxthorn(Lycium chinense Mill) fruits to tree twigs was determined experimentally at several pulling angles(0$^{\circ}$, 15$^{\circ}$, 30$^{\circ}$,45$^{\circ}$and 60$^{\circ}$) and at different harvesting seasons from August to November 1999 using an universal testing machine. The detachment force of mature fruits of boxthorn decreased as the pulling angle increased and varied with the harvesting season. The detachment force however did not gradually decreased as the harvesting season advanced due to difference of maturity of fruits from one harvesting season to another. Among three varieties of boxthron Cheongyang gugija Cheongyang native and Cheongyang ＃2, the maximum detachment force was 1.24 N at the pulling angle of zero degree. The highest detachment forve(1.29 N) of mature fruits of boxthorn appeared at the harvesting season of August, 1999.

• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.151-158
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• 1997

Tomato (lycopersicon esculentum Mill.‘Sunroad’) seedlings grafted onto the four different rootstocks, ‘Anchor-T’, ‘Kagemushia’, ‘Joint’ and ‘Vulcan’, and fed with different amount of nitrogen were investigated for their susceptibility to the root rot Fusarium wilt (Fusarium oxysporum Schl. f. sp. lycopersici Snyder et Hansen, race J$_3$) disease, plant growth, and fruit quality. The flowering of the first flower cluster was promoted in grafted plants (GP) as compared to non-grafted (NG) ones. The plant height was increased by the grafting, and the growth and stem diameter were enhanced with increased nitrogen levels. Grafted plants were little affected by the Fusarium wilt disease except ‘Anchor-T’rootstock (64.7％ infection). The rate of malformed, underdeveloped, and gray-mold infected fruits were reduced in the grafted plants regardless of the rootstocks. Soluble solid content, sugars, ascorbic acids and organic acids did not show any difference between grafted and non grafted plants, but ascorbic acid tends to be reduced in the high nitrogen treatment. Content of N, Ca and Mg in leaves were greatly increased in the GP grown with high nitrogen level (30kg.㏊$^{-1}$ ).