Carbohydrate composition and key enzymes involved in carbohydrate metabolism were assayed throughout development of Lycopersicon esculentum and L. chmielewskll fruit. Translocation and assimilation of asymmetric sucrose and total soluble solids content was also determined in both species. The data showed that L. chmielewskii accumulated less starch than L. esculentum, and this was related to a lower level of ADPglucose pyrophosphorylase and a higher level of phosphorylase in L. chmielewskii. L. chmielewskii accumulated sucrose throughout fruit development rather than glucose and fructose which were accumulated by L. esculentum. A low level of invertase and nondetectable levels of sucrose synthase were associated with the high level of sucrose in L. chmielewskii. Translocation and assimilation of asymmetrically labeled sucrose indicated that sucrose accumulated in L. chmielewskii fruit was imported and stored directly in the fruit without intervening metabolism along the translocation path. In contrast, the relatively low level of radioactive sucrose found in L. esculentum fruit appeared to arise from hydrolysis and resynthesis of sucrose. The possible relationship between the level of soluble solids and differences in carbohydrate metabolism in sink tissue of the two species is discussed.The harvestable yield of tomato appears to be regulated by the net assimilation rate ofthe crop, the rate ofimport into individual fruit, and sink activity (9). High sink demand can significantly increase the quality of the tomato fruit by high accumulation of soluble solids, an important factor for processing tomatoes. Sugars are the major components of the soluble solids content in tomato comprising approximately 65% of the soluble solids.As reported by Gifford and Evans (6), the processes localized in sink tissue largely determine the distribution of photoassimilate between competing sinks. According to Walker and Ho (16), sink strength of a tomato fruit is principally affected by the sink activity of the fruit. The major mechanisms involved in sink activity are: (a) unloading ofsucrose by the phloem, (b) hydrolysis and uptake ofsugars, (c) biosynthesis and storage ofcarbohydrate (10). It has been suggested (16) that invertase activity may play a major role in regulating the rate of carbon translocation in tomato fruit.

Higher plant inhibitors of fungal polygalacturonases are potential contributors to plant defense. To test this hypothesis we have raised antibodies against the `Bartlett' pear fruit polygalacturonase inhibitor (PGIP) and cloned a pear fruit PGIP cDNA. The pear PGIP cDNA was isolated by polymerase chain reactions based on our amino acid and nucleotide sequence information. Sequence analysis predicts a gene product of 34.5 kD with an isoelectric point of 6.02 in agreement with our biochemical data. Seven potential glycosylation sites are consistent with the glycoprotein character of these PGIPs. Southern blot analysis suggests the presence of 1 or 2 genes in the pear genome. Northern blot analysis indicates the presence of a transcript of 1.5 kb. Western blot analysis shows cross-reactivity of the anti-pear PGIP antibody to various dicot species as well as corn.

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FERTILIZATIONPrior to this paper, the latest publication of the detailed data from the two-fifteenths acre plats (Nos. 23, 25, 27, and 29) herein involved was Bulletin I6o of the Rhode Island Experiment Station. In that bulletin was summarized the results from I893 to I9I4, especially the comparative effect of lime on different kinds of plants.In addition to liberal amounts of phosphoric acid and potash, plats 23 and 2 5 annually have received nitrogen in sulfate of ammonia, and plats 27 and 29 the same amount in nitrate of soda.The average annual application during the 34 years has been nitrogen, 49 pounds; phosphoric acid, I I 2 pounds; and potash, I o 5 pounds; or an equivalent of I,2oo pounds of a 5:8:8 fertilizer.During the war period a total of I, 42 5 pounds of common salt was used to supplement unusually small applications of potash. Magnesia was added in various sources from time to time to guard against a possible deficiency. Acid phosphate was the source of phosphoric acid, and muriate or sulfate the usual sources of potash. NQ attention has been given to supplying manganese, although it is now known that in some of the earlier years of the experiment, but only on the nitrate plat which had been limed to neutrality, the chlorosis then observed must have been due to a deficiency of available manganese. LIMING AND SOIL REACTIONUp to I9I5, plats 25 and 29 received an equal amount of lime, but plats 23 and 27 did not receive any lime.In I9I4, t~e pounds of calcium oxid required to neutralize an acre-foot (3,r6o,ooo pounds of the dry surface soil) by the Veitch method were as follows: Unlimed sulfate plat 23, 7,784: limed sulfate plat 25, 4,6o7; unlimed nitrate plat 27, 4,210; and limed nitrate plat 29, 3 ,069. In I9I2, even a low lime-response crop like potatoes was markedly influenced by the greater need of lime with sulfate of ammonia than with nitrate of soda. The bushels per acre were as follows: Plat 23, 128; plat 25, 226; plat 27, 368; and plat 29, 356. Up to I9I5, there had been applied alike to plats 25 and 29 an equivalent of 6,350 pounds of calcium oxid per acre, or an average of 'Contribution No. 352 of the Rhode Island Agricultural Experiment Station, Kingston, R. I.

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The land upon which the experiment was conducted adjoins the college property on the north and was leased from E. Sweet. :rhe soil is classified as Warwick sandy loam, of which there is considerable easily tilled area in the State. The field had not been tilled, cropped, nor m<;~-nured for many years. The turf had become very thin, and moss had taken the place of grass to such an extent that a season's growth did not yield a quarter ton of hay. The subsoil was a coarse gravel, and leaching could take place readily. Aside from manurial requirements, the hmdamental needs appeared to be for lime and for organic matter to conserve moisture. Six apparently uniform, level plats of a quarter acre each were used in the experiment, which was begun in I9I3.The plan was to prepare in different ways for a uniform planting of potatoes in I9I7, with the hope that the effect of the various procedures might be shown on this cash crop. Winter wheat was sown uniformly following the potatoes and harvested in I9I8, after which the station gave up the land. The general cropping system followed on the diff~rent plats will now be described briefly.On plat I, the plan was to grow on the acid soil such crops as might develop there, with the main object of increasing the organic matter. They comprised lupine for green manuring, followed by. rye as a cover crop, in I9I3; soybeans for green manuring in I9I4, followed by redtop in the fall and alsike clover in the spring; this, on account of failure, was replaced by corn in I9I5. At the last cultivation of the corn, grass and <;:lovers were again sown, to be harvested for hay in I9I6.On plat 2, lime was used more liberally and corn planted in I9I3, in which grasses were seeded, supplemented by a seeding with clover the next spring. Hay was. harvested each year until the turf was turned under in the autumn of I9I6 in preparation for the potatoes in l9I7.

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