H.—34

Sturmer. N, unbalanced by P and K, again adversely affected storage quality by increasing the incidence of breakdown, superficial scald, and to a limited extent fungus. The inclusion, of Pto a large extent rectified the position, while the complete treatment, including potash, conferred a storage quality equal on balance to that of the untreated control fruit. Such small differences as did exist showed the complete-treated fruit to have less breakdown and wilt, but more scald, than the control fruit. Cold-storage Quality of Coloured Strains of Apples Delicious.—This year sufficient fruit has been obtained from trees grafted with various red strains of Delicious at the Appleby Research Orchard—eighteen types in all —to enable a small sample to be obtained for cold-storage tests. The indication is that most of the types are distinctly inferior to the standard Delicious in storage quality, some being highly susceptible to breakdown, fungous rots, mouldy-core, or superficial scald. One type of Eichared Delicious, however, was outstandingly good, and one other apple described as a Red Delicious Sport was equal overall to the standard type. Cox s Orange Pippin. 1 hree samples of Red Cox and three of Bledisloe Cox all proved inferior to the standard type in storage quality. The Bledisloe Cox appeared very variable, one sample being only slightly inferior to the standard Cox and another being much the worst of any of the types. Jonathan. —Only two variants of the standard type are available at Appleby, one a Red Jonathan (also known as the Kapai Jonathan) and the other a Pink Jonathan. The former was only very slightly inferior to the standard type in keeping-quality, but the Pink Jonathan was distinctly inferior. It has, moreover, a very unattractive appearance. Dougherty — Two samples of Red Dougherty were compared with a standard type. One appeared to be only slightly inferior to the standard in respect of fungus, ripe-spot, and wilt, but the other developed a substantial amount of ripe-spot as well as a small amount of severe breakdown. It is to be noted that the data recorded for red strains are based on only single half-case samples and are therefore to be considered as tentative and subject to confirmation in succeeding seasons. Effect of Rootstock on Cold-storage Quality Fruit from the rootstock area at Appleby was again subjected to storage test, although the results with East Mailing types XII and XV are still invalidated by the fact that these trees are not yet in full bearing, except with the scion variety, Jonathan. It is possible, however, to get some further preliminary comparisons between MI and Northern Spy, although the results must still be regarded as tentative. Cox's Orange Pippin.—On M I this variety at present has very much better storage quality than on Northern Spy. Differences are very marked in respect of breakdown, fungus, ripe-spot, and pit. Jonathan.—The tentative nature of the current observations is clearly shown by this variety. In the previous annual report it was noted that this variety on M XII was less subject to breakdown than when on the other three stocks under test. This season, however, there have been no significant differences in breakdown susceptibility. On balance, M XII has been rather inferior, chiefly because of a higher incidence of ripe-spot and other fungi. Delicious.—With the Delicious it appears at present that Northern Spy is less satisfactory than Ml or M XV from the storage-quality standpoint, particularly as regards liability to fungous attack and proneness to mouldy-core. On M XII the crop is too light to give a valid comparison. Granny Smith—With this variety only M I and Northern Spy can bo considered comparable, from the crop-weight standpoint. The present position is that M I has conferred a considerably greater resistance to superficial scald and to core-flush than has Northern Spy. It may be noted without prejudice that fruit on M XV has kept as well as that on Northern Spy, although the M XV trees carried less than one-third the crop of the Spy trees. FRUIT RESEARCH Advisory Committee.—Sir Theodore Rigg (Chairman), Dr. G. H. Cunningham, Messrs. W. Benzies, T. C. Brash, F. R. Callaghan, J. Corder, W. K. Dallas, E. J. Fawcett, Hope B. Gibbons, A. Osborne, R. Paynter, A. M. Robertson, H. E. Stephens, and L. W. Tiller (Secretary). Investigations have been continued at the centres shown below, although the scope of the work continues to be somewhat restricted by shortage of staff on account of the war. The fruit industry is probably unique in the wide range of sciences encompassed in its problems, and a full study of all its difficulties would necessitate a staff many times larger than is at present available. Nevertheless, a wide field of work has been covered and much information of value to the industry has been obtained. Research Orchard, Appleby (a) Long-term Manurial Investigations.—'These are now in their fourteenth year from commencement of treatment, and in general the results of the present season support previous indications that the best results arc obtained when phosphate, potash, and nitrogen are all provided for apple trees growing on the Moutere Hills soil. Evidence is accumulating that the use solely of nitrogen can cause decline of trees and render them susceptible to attack by destructive fungi. A brief indication of the economic significance of the effect of various fertilizers, in terms of weight" of fruit produced per tree during the season under review, is given below. "N " indicates " treated with ammonium sulphate," "P " signifies " treated with superphosphate," and "K " signifies " treated with sulphate of potash." Throughout the experiments, foliage and shoot development follow closely the yield responses. Cox's Orange Pippin : N trees produced 97 lb., or 59 per cent., more than untreated controls, and PNK trees produced 119 lb., or 73 per cent., more than the controls. PK trees appeared to carry a little more fruit than the controls, but the difference is not statistically significant. Dunn's Favourite : N trees produced 49 lb., or 22 per cent., more than the controls, and PNK produced 87 lb., or 38 per cent., more than the controls. Delicious : PNK trees produced 30 lb., or 25 per cent., more than the controls, but N trees produced 25 lb. less than the controls. Owing, however, to extreme variation in the cropping of individual trees this season the observed differences in average yield between treatments are not statistically significant.

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