Top Fresh Weight Research Articles

Studies on the salt tolerance of vegetable crops in sand culture. II

As part of the studies on the salt tolerance of vegetable crops, seven leaf vegetables, namely, cabbage, spinach; Chinese cabbage, celery, onion, lettuce, and Japanese hornwort, were grown in sand cultures under glass at various concentrations of NaCl. HOAGLAND's solution was used as the basic solution (control), and the concentrations of NaCl added to it were 1000, 2000, 4000, 8000, and 16000ppm, respectively. 1. In spinaches, onions, lettuces, and Japanese hornworts, plants were dwarfed, and both the number of leaves and the fresh weight of tops were reduced with increasing concentration of NaCl. In cabbages, and celeries, however, the 1000 or 2000ppm treatment had favorable effects on the growth of plants and the fresh weight of tops. The plants died at the 16000ppm in Chinese cabbages and lettuses, and above 4000ppm in Japanese hornworts. The concentration of NaCl in the nutrient solution corresponding to a 50 per cent reduction in the fresh weight of tops was found to be about 9000ppm for cabbages, 8000ppm for spinaches and Chinese cabbages, 6000ppm for celeries, 2500ppm for onions, 2000ppm for lettuces, and 1000ppm for Japanese hornworts. In cabbages, the hard formation was a little delayed with the increase of salinity, and the heads at the 8000 and 16000ppm were less compact than those from the lower salt treatments, then the yield of heads was reduced by 50 per cent at about 6500ppm. In onions, bath the bulb formation and the maturing were not affected by salinity, except the 16000ppm treatment in which growth was especially poor, and the yield of bulbs was reduced by 50 per cent at about 2500ppm. In some crops, the dry weight percentage of tops increased slightly in higher salt treatments. 2. Specific symptoms of salt injury were as follows: In cabbages, the surface of leaves was temporarily waxy in the treatments above 2000ppm. In spinaches, leaves were entirely chlorotic at the 16000ppm. In Chinese cabbges, leaves were dark bluish green above 8000ppm, the plants died at the 16000ppm, and incurling of leaf margins generally occurred in all NaCl treatments. In onions, die back of leaves occurred starting from the older leaves in the NaCl treatments, which caused the complete die off of the leaves at the 16000ppm. In lettuces, leaves were dark green at the 4000 and 8000ppm, while leaves were entirely chlorotic and subsequently the plants died at the 16000ppm. Celeries and Japanese hornworts developed no specific symptoms, but the latter died above 4000ppm. 3. With increasing cocentration of NaCl in the nutrient solution, both Na and Cl were accumulated proportionaly in the leaves of most crops, and more tolerant crops tended to accumulate more Na. Except in Japanese hornworts, Na accumulated in leaves in greater equivalent amounts than Cl. In general, antagonistic relations were found between Na and other cations, i.e. K. Ca and Mg, intensity of which, however, varied with the ions or vegetables, and the total amount of these four cations in leaves increased with increasing of NaCl in culture solution in most crops. The contents of N in leaves, except in cabbages, tended to decrease in the NaCl treatments. The effect of the NaCl treatments on the contents of P in leaves was variable with the vegetable species. But the variation of the contents of N and P was rather slight as compared with that of cations. There was no such definite tendency in the variation of carbohydratee contents in leaves.

Studies on the blindness in gladiolus. VII

A study was made to know the effect of nutritional contents in corms on the flowering in gladiolus. Corms of the variety Spotlight, which were shown in Table 1, were planted in benches containing sandy soil in the experimental greenhouse at Kagawa University on March 19, 1959, and they were grown with water alone (no fertilizer was added). Number of germinated corms, date of flowering, number of plants died, number of blind stalks, and number of flowered plants were recorded. On July 31, all plants were dug up, and fresh weight of tops, fresh weight of corms, and number of cormels were recorded. Cormels of the same variety which were shown in Table 3 were planted in the same greenhouse on March 20, and they were dug up on June 4, and the fresh weight of the plants was measured. The reasults obtained are summarized as follows: 1. Earlier flowering was observed in the plants to which N 100 ppm and P 25-50 ppm were applied in the previous year, and later flowering in -N plants or the plants to which N 200 ppm alone was applied. 2. Percentage of germination and percentage of flowering were high in the plants to which nitrogen was applied in the previous year, and percentage of plants died and percentage of blind stalks were high in -N plants. Several malformed plants were observed in the plot in which N 200 ppm alone was applied. 3. Number of florets, height of plants, fresh weight of tops, fresh weight of corms, and number of cormels were increased. 4. No significant differences were observed in the number of leaves and fresh weight of cormels. 5. From the results above mentioned it seems that the most superior was the plant to which N 200 ppm and P 50 ppm were applied in the previous year, and the nutritional contents in these corms were 1.99% of nitrogen, 0.31% of phosphorus and 0.57% of potassium in dry matter. The second was the plant to which N 200 ppm and P 25 ppm were applied, and 1.82% of nitrogen, 0. 22%of phosphorus, and 0.49% of potassium were contained in corms.

Studies on the blindness in gladiolus. VI

A study was made to clarify the problem “nutri-tion and blindness” in gladiolus. According to the design showh in Table 1. three corms each of Spot-light variety (average weight 25. 7g) were planted in sand in Wagners pots on May 26, 1958 and nutritional treatments were made from June 17 to September 13 at 3 day intervals during the course of experiments. Samplings for the chemical analysis were made at the time of flowering, August 21, and at the time of digging, November 5, 1958. Date of flowering, height of plants, number of leaves, and number of florets were recorded at flowering time. Fresh wegihts of tops, of new corms, and of cormels, and number of cormels were measured at digging time. The results obtained are summarized as follows: 1. No significant differences were observed in percentage of flowering, height of plants, number of leaves, and number of florets, even though there were a few blind stalks in -N and several other plots. 2. Earlier flowering was observed in the plots treated with N 200_??_100 ppm and P 50 ppm, and later flowering in -N plots. 3. The color of leaves in the plots supplied with N 50 ppm or -N was yellowish-green, which clearly showed the N deficient symptom, and these plants. showed weaker growth than the others. In the plots: of N 200ppm, the color of leaves showed dark greenb and the plants looked vigorous, but the color of roots: was dark brown and the development of root system, was poor. 4. Fresh weight of tops and of new corms were increased with an increase of nitrogen. 5. Number of cormels was increased in the plots-supplied with low level nitrogen, and decreased remarkably in N 200ppm plots. There was no significant difference in the fresh weight of cormels. 6. Absorption of nitrogen increased with increas-ing of nitrogen supply regardless of application ra-tes of phosphorus or potassium. With increasing of phosphorus increased not only P absorption but also N absorption, except the plot supplied with phos-phorus alone. With increasing potassium increasedi K absorption-slightly when it was supplied with P 25_??_50 ppm or N 100 ppm, and decreased when it was supplied with N 200 ppm. 7. From the results mentioned above, it seemss that nitrogen has a strong relation to flowering in gladiolus, and the optimum of nitrogen application in flowering is 100 ppm. And phosphorus promotes. the effect of nitrogen.

Studies on the salt tolerance of vegetable crops in sand culture. I

From 1957 to 1960, vegetable crops were grown in sand culture under glass at various concentrations of NaCl to study their relative salt tolerance, visual symptoms of salt injury, and effect of NaCl on absorption of nutrient elements and carbohydrate content of plants. HOAGLAND's solution was used as the basic solution (control), and 1000, 2000, 4000 8000, or 16000 ppm of NaCl was added to it. The present paper, as a part of the studies, deales with the results of experiments on six fruit vegetables, namely, tomato, pepper, cucumber (the 1000 ppm treatment was omitted), broad bean, snap bean (the 100 and 16000 ppm were omitted), and strawberry. 1. With increasing concentration of NaCl, plants were dwarfed and the emergence of lateral shoots was restricted. Concentrations of NaCl above 8000 ppm in cucumbers, broad beans, and snap beans, and above 4000 ppm in strawberries caused severe dying off of older leaves and finaly death of entire plant. With the increase of NaCl, the fresh weight of tops (vines) was reduced, excpet that tomatoes showed the greatest weight at the 1000 ppm treatment The yield of fruits, however, was reduced in any crop with the increase of NaCl. The concentrations of NaCl in the solution corresponding to a 50 percent reduction in yield of fruits of tomatoes, peppers, cucumbers, broad beans, and strawberries were about 3500, 3000, 3000, 2500, 2000, and 1000 ppm, respec-tively. In tomatoes, and peppers, the reduction in yield of fruits was more significant than that of vines. The dry weight percentage of tops generally decreased in high salt treatments. 2. The number of flowers tended in general to parallel declining vegetative growth as salinity in-creased. The rate of fruit setting was reduced mark-edly in the treatments above 8000 ppm in tomatoes and above 4000 ppm in peppers. In most crops, the dates of first flower opening and of first harvesting were not so remarkably affected by NaCl treatments, but in peppers, severe shedding of early fruits in higher salt treaments retarded the first harvest. No apparently harmful effects of NaCl treatments were observed on the fertility or germination percentage of pollens, and on the seed set. 3. Symptoms of salt injury were as follows: In tomatoes, leaves were dark green from 1000 to 8000 ppm, but were chlorotic at the 16000 ppm. In pep-pers, leaves were chlorotic and leaf margins incurl-ed at the 16000 ppm. In cucumbers, above 8000 ppm, leaf margins incurled and interveinal chlorosis occurred starting from older leaves before the death of the plant. In snap beans, leaves were dark green at the 2000 and 4000 ppm, while at the 8000 ppm older leaves developed severe burn between veins before the death of the plant. In strawberries, severe mar-ginal burn occurred in older leaves and petals were greenish at the 2000 and 4000 ppm. Blossom-end rot occurred to a high degree at the 1000 ppm and above 8000 ppm in tomatoes, and at the 2000 ppm in pep-pers. Broad beans developed no specific symptoms. 4. With increasing concentration of NaCl, the accumulation of Na in leaves increased almost linearly, except in peppers and snap beans, while Cl accumu-lated linearly in any crop. Cl accumulated in leaves in greater equivalent amounts than Na except in broad beans. Antagonistic relations between Na and other cations, i. e. K, Ca, and Mg, varied with ions or vegetables, and the total amount of these four cations in leaves decreased in peppers and snap beans and increased in the others with the increase of NaCl. The variation in the content of N or P was rather slight as compared with cations and was variable with the vegetable species. There was no definite tendency in the contents of carbohydrates.

Influence of the methods of treating soil in planting hole on the growth of young chestnut trees

This experiment was carried out to study the effect of methods of treating soil in planting hole on the current year growth of young chestnut trees planted in the hole. Large planting holes of 120cm in diameter and 90cm in depth were dug and: refilled with the soil in the following procedure. Plot 1. Each layer of soil was returned to its original position: surface soil to the top layer, subsoil to the bottom. Plot 2. The surface soil was placed in the bottom of the hole and the subsoil in the top. Plot 3. The hole was refilled with the mixture of surface soil and subsoil. Plot 4. The hole was refilled with the surface soil only. Plot 5. Large holes were not dug. Young trees were set in the small holes just large enough for planting the trees. A one-year-old chestnut tree (var. Ginyose, a leading variety in Japan) grafted on free stock was planted in the center of each hole. The measurement at the end of current growing season revealed that trunk circumference was largest in Plot 1, followed by Plot 4 and 5, 3 and 2 in the order. It continued to increase until later in the season in Plot 1 and 4 than in the other plots. Total shoot length was longest in Plot 1 and 4, medium in Plot 3 and shortest in Plot 2 and 5. Shoot elongation ceased earliest in Plot 2 and 3, later in Plot 4 and 5, and did not stop by late fall in Plot 1. The top fresh weight after leaf fall was heaviest in Plot 1, followed by Plot 4, 5, 3, and 2 in the order. One representative tree each from Plot 1, 2 and 3, respectively was excavated to observe its root system. Roots in Plot 1 penetrated to the deepest layer, and roots in Plot 3 to the shallowest, while there was no significant difference in the extent of lateral spread of root system among the plots. Leaf samples were collected four times during the growing season for leaf analyses. Little difference was found in N and P contents among the plots, but a positive correlation was found between K content in the leaves and growth. Chemical properties of each layer of the soil were determined, and porosity of the soil in the planting holes was measured. From these data it is suggested that the growth of young chestnut trees was affected not only by the physical properties of soil but also by its chemical properties, and poor growth in the current year in the plots, where subsoil was brought to the top layer, might be due to the poor fertility of that layer.

Contratoxification of Plant Growth-Regulators in Soils and on Plants

1. 2,4-Dichlorophenoxyacetic acid (2,4-D), butyl ester of 2,4-D (BE 2,4-D), copper, 2,4-dichlorophenoxyacetate [Cu(2,4-D)2], 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), and O-isopropyl N-phenylcarbamate (IPPC) were added on June 6, 1946, to separate aliquots of silt loam soil at concentrations of 22 and 220 p.p.m. About two-thirds of each aliquot was placed in storage and occasionally moistened. The remaining one-third of each aliquot was placed in 5-inch glazed crocks and planted uniformly with Red Kidney beans, white mustard, and barley to test the degree of toxicity of the compounds by later emergence of the plants. Soil was removed from storage on June 27 and November 16, 1946, and May 7, 1947, and similarly planted to test for degree of toxicity of the compounds. The soil planted on May 7, 1947, was replanted on September 2, 1947. 2. In this greenhouse experiment much of the toxicity of IPPC, the least persistent compound used, had disappeared after 12 days of storage. Soil originally containing 220 p.p.m. of 2,4,5-T was still toxic after about 15 months of storage. Cu(2,4-D)2, 2,4-D, and BE 2,4-D disappeared with about equal rapidity. Soil containing these three compounds at initial concentrations of 22 p.p.m. showed little toxicity after 11 months of storage; soil containing them at 220 p.p.m. had lost its toxicity after 15 months. 3. 2,4-D was added to plots in a lowland soil at a rate of 7.4 lb/acre, and Cu(2,4-D)2, 2,4,5-T, and BE 2,4-D were added to other plots at chemically equivalent rates. Successive plantings of Sudan grass, Red Kidney bean, white mustard, and soybean were made. Emergence of plants and fresh weight of tops were used as criteria for judging the toxicity in the soil. 4. In this field experiment 2,4,5-T proved to be the least toxic and persistent, and BE 2,4-D the most persistent. The treated soils were still considerably toxic 45 days after application of the growth-regulators. 5. 2,4,5-T brought about poor control of weeds, Cu(2,4-D)2 and 2,4-D fair control, and BE 2,4-D excellent control. 6. Spading (plowing) resulted in a great decrease in toxicity in a field soil contaminated with 2,4-D. When 10 or 25 lb. of 2,4-D per acre were applied to a field soil, only the upper 3 inches of soil were toxic to plants even after heavy rains. 7. Addition of Zeo-Karb H or Norit A to soil containing 2,4-D resulted in a decrease or in complete elimination of toxicity. In a greenhouse experiment addition of Norit A at a concentration of about 218 p.p.m. decreased the toxic effects of 2,4-D present in the soil. 8. Finely ground Norit A or Zeo-Karb H was dusted or sprayed in aqueous suspension on Red Kidney bean, soybean, white mustard, or marigold. The plants were then sprayed with aqueous 0.1% solutions of ammonium 2,4-dichlorophenoxyacetate, sodium 2,4-dichlorophenoxyacetate, triethanolamine salt of 2,4-D, isopropyl ester of 2,4-D, or BE 2,4-D, or were dusted with a dust containing BE 2,4-D. In most cases the toxic effects of the growth-regulators were greatly decreased or completely eliminated by Norit A or Zeo-Karb H. 9. Super filtrol and attapulgus clays were ineffective as contratoxicants Lamp black and bone black were partially effective. 10. The addition of the base mixture of Weed-No-More as a wetting agent to suspensions of contratoxicants often decreased or eliminated their effectiveness. 11. Red Kidney beans were sprayed with a 0.1% solution of BE 2,4-D and at various intervals after treatment were sprayed with aqueous suspensions of Norit A or Zeo-Karb H. Unless the contratoxicant was applied within 15 minutes after treatment with the growth-regulator, very little protection was afforded. 12. A 5% aqueous suspension of Norit A heavily sprayed on young Red Kidney beans gave good protection against sprays of growth-regulators. A larger amount of Zeo-Karb H was required for equal protection.

Effect of Spray Applications of 2,4-Dichlorophenoxyacetic Acid on Subsequent Growth of Various Parts of Red Kidney Bean and Soybean Plants

1. Plots containing young red kidney bean and soybean plants were sprayed with 2,4-dichlorophenoxyacetic acid at rates of 0.1, 0.01, and 0.001 gm. per sq. yd. The effects of the agent on the growth of various plant parts were studied. Linear, and fresh and dry weight measurements were obtained at several intervals following treatment. 2. Hypocotyls and first internodes increased greatly in diameter. The increase in fresh weight was due mostly to increased water content. 3. Primary leaves of treated plants were much heavier than those of controls. Those of red kidney beans remained green and attached to the plants long after those of controls had withered and fallen. 4. Total weights of trifoliate leaf blades, trifoliate leaves, and weight of plants above second node were decreased by the growth regulator. There was good correlation between decrease in weight and increase in amount of compound applied. These criteria would be excellent in studying the relative inhibitory or stimulating actions of growth regulators on red kidney beans. Ten days after treatment there were highly significant differences between controls and treated plants, and between treated plants, when fresh weights of trifoliate leaves or leaf blades were used as criteria. The differences were significant when the fresh weight of kidney bean plants above the second node was used as a criterion. With soybeans, only fresh weight of trifoliate leaf blades gave significant differences between controls and treated plants and between plants that received various rates of compound when plants were harvested 21 days after treatment. 5. The growth in length and width of certain leaflets which developed after treatment was inhibited by the growth regulator. The two higher levels of compound (0.1 or 0.01 gm. per sq. yd.) inhibited the linear growth of certain petioles. The lowest level (0.001 gm. per sq. yd.) stimulated growth in length of a soybean petiole but had little effect on a bean petiole. 6 The fresh weight of tops was decreased by the growth regulator. Heights were usually decreased but differences caused by various treatments were sometimes small. 7. The compound at rates of 0.01 and 0.1 gm. per sq. yd. decreased dry weight of roots of kidney bean, but 0.001 gm. had little effect. With soybeans the two lower rates of application significantly increased weight of roots at 16 days after treatment. However, by 21 days the weight of control roots was about the same as that of the treated plants. 8. With kidney beans there was little effect on the shoot-to-root ratio when two lower amounts of the compound were used. With soybeans, the ratio was reduced by all treatments. 9. The growth regulator delayed the onset and decreased the amount of pod formation.