TABLE 2. Yield and growth characteristics of four donal plantains. HORN PLANTAIN DWARF PLANTAIN TALL FRENCH DWARF FRENCH 1ST 2ND IST 2ND 2ND 2ND CHARACTERISTIC HARVEST HARVEST HARVEST HARVEST Yield (tons/ha) 16.1 14.4 20.3 23.9 31.5 46.0 Average wt. bunch (Kg.) 9.2 8.25 11.6 13.7 18.04 26.3 Fruits/bunch 31 35.5 34.8 57 92 130 Fruits/ha 54,002 61,841 60,621 99,294 160,264 226,460 Height at shooting (m) 2.5 3.2 2.1 2.44 3.35 1.95 Stem width (cm) 15 14.2 19.6 20.83 17.8 19.05 Days to shooting 326.2 549 338.5 541.5 588 579 Days from shooting to harvest 71.4 76.4 78.2 77 84.7 99 Number of leaves at harvest 11.6 11.12 13.5 14.3 13 11.8 TABLE 3. Nutrient deficiency and disease ratings' of four clonal plantain varieties. VARIETIES IRON DEFICIENCIES2 K DEFICIENCIES2 WET ROT3 'Horn Plantain' 4 4 4 JTall French' 3 2 0 IDwarf Plantain' 2 1 0 /Dwarf French' 2 1 0 1. Visual symptoms on a scale of 1 (no deficiencies or disease) to 5 (severe deficien- cies or disease). 2. Iron deficiency-chlorosis of leaf, mainly younger leaves. Potassium deficiency-marginal chlorosis gradually moving to mid-rib, occur- ring mainly on older and middle leaves. 3. Pseudostem wet rot (Erwinia sp.)- blackening, and gradual rotting and col- lapse of mid-pseudostem leading to collapse of plant. Mean yield and growth characteristics of the first two harvests of the four varieties are represented in Table 2. The French varieties are represented by only one harvest, the first ratoon, since, although reversion started in the plant crop, it was not quite distinct at that time. Table 2 also indicates that the two French types produced relatively higher yields and more fruits per bunch than the original two varieties. The variant 'Dwarf French' outyielded the other TABLE 4. Mean number of major nematodes extracted from 100 cc of soil from rhizosphere of plantains grown from explants and treated with nematicides. TREATMENTS ROOT KNOT SPIRAL RENIFORM TOTAL POPULATION FURADAN 5%G 6 107 164 277 TEMIK 10%G 0 82 181 263 DIAZINON 2E 3 79 192 274 CONTROL 19 108 133 260 z Furadan applied at 4 month, Temik at 6 month and Diazinon at 2 month intervals. Furadan and Temik not applied during flowering and fruiting. Nematode assays taken at 2 intervals in crop life. Laboratory diagnosis done in cooperation with the Univ. of Georgia, Athens. varieties, averaging 46.0 tons/ha or 226,460 fruits/ha. It produced 130 fruits/bunch compared with 31 for the 'Horn Plantain.' On the other hand, the 'Horn' and 'Dwarf Plantains' took less days to shooting and less days from shooting to harvest. The 'Tall French' was the tallest at shooting at 3.35 m and the 'Dwarf French' the shortest at 1.95 m. The dwarf types also had thicker pseudostems, so were more sturdy, wind resistant and required less staking. Table 3 gives a visual rating of symptoms of nutrient deficien- cies and diseases observed among the four varieties. It indicates that the 'Horn Plantain' was severely affected by iron and potassium deficiencies and pseudostem wet rot disease (Erwinia sp.). On the other hand, the two dwarf varieties were more resis- tant to these nutrient deficiencies and wet rot disease. The tolerance to a high pH soil and resistance to disease or nutrient- induced disease shown by the French types is a good indicator of their adaptability to local soil and climatic conditions. Table 4 presents the total population and distribution of major nematodes found in soil assays. Of major significance is the total absence of the burrowing nematode (Radapholus similis), since this pest has always been recovered from banana and plantain soil assays (Ayala and Roman, 1963). The use of tissue cultured plants may be partly responsible for this notable lack of Radapholus. Nematicides and Diazinon 2E apparently effectively controlled root knot nematodes with major effects on reniforn and spiral types. Since the occurrence of nematodes apparently did not reduce yields and plant growth, further trials with clonal material may not necessitate use of these pesticides. Acknowledgements The authors are extremely grateful for the long term assistance of Dr.Roy Mots- inger, Nematologist at University of Georgia, Athens, for the analysis of nematode samples. References 1. Ayala, A., andJ. Roman. 1963. Distributions and host range of the burrow- ing nematode in Puerto Rican soils. J. Agric. Univ. P.R. 47(1):28-37. 2. Berg, L.A., and M. Bustamante. 1974. Heat treatment and meristerm culture for the production of virus free bananas. Phytopathology 64:320-322. 3. Irizarry, H., J.A. Rodriquez, and N. Diaz. 1981. Effect of three population densitites and fertilizer levels on yield of high yielding clones of plantain at two loca- tions. J. Agric. Univ. P.R. 65(4):395-400. 4. Irizarry, H., J.A. Rodriguez, and D. Oramas. 1979. Evaluation of four nematicides in preplant treatments of plantain (Musa acuminata Xm. balbisiana, AAB CV. Marigongo) corms. J. Agric. Univ. P.R. 63(2):269-271. 5. Ittyeipe, K. 1983. Plantain production in the West Indies. The Banana Company ofJamaica Ltd. P.O. Box 602, Kingston, 10 S. Ave., Kingston 4,Jamaica, W.I. 6. Martinez, R.G. 1981. Plant parasitic nematodes of the U.S. Virgin Islands with the description, life cycle and morphology of Meloidogyne cruciani N. sp. and its interactions with Rotylenchulus Reniforms. PhD. dissertation, Univ. of Florida, Gainesville, FL. 7. Vuylsteke, D. 1983. Propagation of banana and plantains by shoot tip culture in vitro. Banana Newsletter No. 6. International Group on Horticultural Physiology of Banana. 8. Walmsley, D. 1974. Mineral nutrition of two plantain (Musa, AAB Group) cultivars of the French and Horn type. Proc. C.F.C.S. 12:141-156. PROCEEDINGS of the CARIBBEAN FOOD CROPS SOCIETY-VOL. XX 244