Kola (Cola nitida) is an important economic cash crop for many West and Central African countries. It has several medicinal uses in the pharmaceutical industries and also plays a major role in traditional marriages am...Kola (Cola nitida) is an important economic cash crop for many West and Central African countries. It has several medicinal uses in the pharmaceutical industries and also plays a major role in traditional marriages among Islamic communities across West and Central Africa. The crop is extensively cultivated in Nigeria and Ghana. However, it exhibit signs of total and partial sterility as well as self incompatibility when propagated from seeds in most cases. Therefore, grafting is seen as a method of choice in addressing the problem stated above. Though grafting accounts for some degree of success, there is the need to assess genotypic and physiological factors that account for high or low grafting success. Genetic and physiological factors (such as rootstock age) affecting grafting success and growth in kola (C. nitida) were investigated in two separate experiments. In experiment I720 kola seedlings were raised from unselected kola nuts and sown at two monthly intervals. Four groups of seedlings (180/group) i.e. 6, 8, 10 and 12 months old were thus produced. Three different scions (A1, A12 and JB1) measuring (5-10 cm) were grafted onto the four age groups of rootstocks, namely, 6, 8, 10 and 12 months. Experiment II consisted of 540 seedlings raised from three main crosses (JX1/9 × JX1/11 * B1/142 × B1/151, JX1/9 × JX1/11 * B2/177 × B2/156 and JX1/9 × JX1/11 * GX1/46 × GX1/53). Grafting was done after six months using the same set of scions as described in experiment I. Experimental design used was 3 × 4 and 3 × 3 factorial designs in completely randomised design with three replicates for experiment I and II respectively. The fixed effects were the different genotype and age of rootstock at grafting whilst the response variable was the percentage of successful grafting two months as well as growth at six monthly intervals. Results from the study showed that grafting onto 6 months old stocks gave the highest percentage success and growth of grafts followed by 8, 10 and 12 months old rootstock in that order in both trial years. The study revealed also a significant rootstock and scion interaction (P < 0.05). We conclude that successful grafting in kola depends on rootstock genotype such as JX1/9 × JX1/11 * GX1/46 × GX1/53 and has been proven suitable for use in future kola propagation studies. Nonetheless, suitable rootstock with high grafting success does not translate into vigorous scion growth.展开更多
The scion cutting mechanism of the traditional grafting machine cannot correct the bending degree of the scion seedling stem so that the cutting angle of the scion seedling is not standard and the survival rate of the...The scion cutting mechanism of the traditional grafting machine cannot correct the bending degree of the scion seedling stem so that the cutting angle of the scion seedling is not standard and the survival rate of the grafted seedling is affected.In this study,cucumber seedlings and watermelon seedlings were taken as experimental objects.Based on the analysis of the geometric parameters and mechanical characteristics of scion seedlings,a scion cutting mechanism with holding seedling applied to cucumber seedlings and watermelon was designed and developed.The main structure and operating parameters of V-shaped holding seedling block and cutting unit were determined,and holding seedling and cutting performance tests were carried out.The test results showed that compared with the common arc clamp,the V-shaped holding seedling block had a better guiding and centering effect on the scion seedling,could better correct the bending state of the scion seedling stem,and the success rate of holding seedling of the V-shaped holding block reached 98.33%,which was increased by 13.33%compared with the arc-shaped clamp,and the seedling injury rate was only 1.67%.The upper and lower two-point positioning of scion stem by clamping hand and holding seedling block can improve the cutting performance effectively.The cutting accuracy rate of the scion was 97.75%,and the cutting success rate was 98.67%.The cutting performance was closely related to the holding seedling effect.The research results can provide a reference for the design of cutting mechanisms of melon grafting robots.展开更多
文摘Kola (Cola nitida) is an important economic cash crop for many West and Central African countries. It has several medicinal uses in the pharmaceutical industries and also plays a major role in traditional marriages among Islamic communities across West and Central Africa. The crop is extensively cultivated in Nigeria and Ghana. However, it exhibit signs of total and partial sterility as well as self incompatibility when propagated from seeds in most cases. Therefore, grafting is seen as a method of choice in addressing the problem stated above. Though grafting accounts for some degree of success, there is the need to assess genotypic and physiological factors that account for high or low grafting success. Genetic and physiological factors (such as rootstock age) affecting grafting success and growth in kola (C. nitida) were investigated in two separate experiments. In experiment I720 kola seedlings were raised from unselected kola nuts and sown at two monthly intervals. Four groups of seedlings (180/group) i.e. 6, 8, 10 and 12 months old were thus produced. Three different scions (A1, A12 and JB1) measuring (5-10 cm) were grafted onto the four age groups of rootstocks, namely, 6, 8, 10 and 12 months. Experiment II consisted of 540 seedlings raised from three main crosses (JX1/9 × JX1/11 * B1/142 × B1/151, JX1/9 × JX1/11 * B2/177 × B2/156 and JX1/9 × JX1/11 * GX1/46 × GX1/53). Grafting was done after six months using the same set of scions as described in experiment I. Experimental design used was 3 × 4 and 3 × 3 factorial designs in completely randomised design with three replicates for experiment I and II respectively. The fixed effects were the different genotype and age of rootstock at grafting whilst the response variable was the percentage of successful grafting two months as well as growth at six monthly intervals. Results from the study showed that grafting onto 6 months old stocks gave the highest percentage success and growth of grafts followed by 8, 10 and 12 months old rootstock in that order in both trial years. The study revealed also a significant rootstock and scion interaction (P < 0.05). We conclude that successful grafting in kola depends on rootstock genotype such as JX1/9 × JX1/11 * GX1/46 × GX1/53 and has been proven suitable for use in future kola propagation studies. Nonetheless, suitable rootstock with high grafting success does not translate into vigorous scion growth.
基金This work was financially supported by the Beijing Academyof Agriculture and Forestry Sciences Innovation Ability Project(Grant No.KJCX20180422)the Key Research and Developmentprojects in Ningxia Hui Autonomous Region(Grant No.2018BBF02024)the Nationa1 Key Technology Research andDevelopment Program of China(Grant No.2013AA102406).
文摘The scion cutting mechanism of the traditional grafting machine cannot correct the bending degree of the scion seedling stem so that the cutting angle of the scion seedling is not standard and the survival rate of the grafted seedling is affected.In this study,cucumber seedlings and watermelon seedlings were taken as experimental objects.Based on the analysis of the geometric parameters and mechanical characteristics of scion seedlings,a scion cutting mechanism with holding seedling applied to cucumber seedlings and watermelon was designed and developed.The main structure and operating parameters of V-shaped holding seedling block and cutting unit were determined,and holding seedling and cutting performance tests were carried out.The test results showed that compared with the common arc clamp,the V-shaped holding seedling block had a better guiding and centering effect on the scion seedling,could better correct the bending state of the scion seedling stem,and the success rate of holding seedling of the V-shaped holding block reached 98.33%,which was increased by 13.33%compared with the arc-shaped clamp,and the seedling injury rate was only 1.67%.The upper and lower two-point positioning of scion stem by clamping hand and holding seedling block can improve the cutting performance effectively.The cutting accuracy rate of the scion was 97.75%,and the cutting success rate was 98.67%.The cutting performance was closely related to the holding seedling effect.The research results can provide a reference for the design of cutting mechanisms of melon grafting robots.
