| The wheats from Sind were pure line selections maintained at the Agricultural
Research Station, Sakrand, and their average score appears far too low,
but it is possible that wheats from outside the state are included. The
distribution of individual scores of the Sind wheats suggests heterogeneity
: no other reasonably large sample has had a high proportion of both 0 and
3 scores. Further, two of the wheats scoring 0 were classed as "late" in
ear emergence, which is more characteristic of wheats from high altitudes,
whereas most of Sind is below 200 m. On the other hand the Sind collection included the only clavate (clubbed, not compactum) wheats from the subcontinent. There were 5 of these, not included in Table 1, with an average score of 2,00. Similar wheats came from the highlands of Afghanistan (WRIGHT 1972). Subterminal spikelets : Wheats with at least 5 fertile glumes in the first subterminal spikelets in the 20-ear sample, and with at least 50 percent more fertile glumes in this position than in the terminal spikelet, were shown in the previous study to have a highly non-random distribution : in Afghanistan they were found only in high-altitude regions. Of the 254 wheats in Table 1, 24 were of this type. Although 5 were from Kashmir and 2 from Sikkim, in line with the distribution in Afghanistan, there were 8 from Uttar Pradesh and 4 from Sibi, and even one from Bela, on the coast. There is no pattern in the distribution, except that the proportion is highest in the mountain valleys of the north. Two of the Punjab pure lines, 8A and 17B, were of this type. Among 18 improved wheats from Lyallpur and Pusa (not included in Table 1) there were also two of this type : C. 518, bred from 8A (PAL 1966), and N.P. 90 (not mentioned by PAL). High-level glume fertility : In some wheats fertile glumes are found further down the ear than the top one or two spikelets discussed so far, and generally in most of the spikelets above the lowest affected spikelet. In more extreme cases, including some sub-compactoids, there may be a fairly coherent block of affected spikelets at the base of the ear also. In one Pakistani wheat, "Sind 5", the second glumes of nearly all spikelets were fertile, and in some ears both glumes of the subterminal spikelet were fertile. The presence in the standard sample of at least one ear with a fertile glume below the sixth spikelet is used to define a high level of glume fertility. In Afghanistan this type was rare in all high-altitude areas, and none occurred in the regions in which there was a high ratio of subterminal to terminal spikelet fertility. Only one Indian wheat, from Rewa, achieved this level, though several from adjacent areas approached it. Except for Bela and Chagai, however, there were one or two in each group of Pakistani wheat in Table 1, so that the distribution overlapped that of the subterminal type. Besides "Sind 5" the 6 high-fertility Pakistani wheats included Punjab line 15 and the compactoid-like Sind line 15. |
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