High soil salinity occurs in a large area where sunflower (Helianthus annuus L.) is produced in the USA and limits production capabilities there and in many parts of the world where sunflower is grown, particularly under irrigated conditions in arid climates. A wild species of sunflower, Helianthus paradontsHeiser, was noted to be unusually tolerant to saline conditions. This investigation examined the salinity tolerance of five interspecific germplasm lines derived from crosses of. H. paradorus with cultivated H. annuus and studied the inheritance of salinity tolerance. Preliminary results indicated that three interspecific crosses had tolerance to a 15 (EC. 24.7 dsm-') g/l NaCl solution in both a seedling and germination test. These germplasm lines and a susceptible inbred line were crossed. Segregation ratios of Fz and backcross generations indicâted that one major dominant gene, proposed as Sar, controlled seedling tolerance to salinity. A recessive modifier gene also appeared to be affecting seedling tolerance to salinity. In the germination study, no single gene was clearly identified for control of tolerance to salinity; however, a level of tolerance was found and appeared to be dominantly controlled. These seedling and germination procedures will be further tested to determine their utility in breeding programs desiring increased tolerance to soil salinity.

Pathogen efficient analysis study was conducted under normal (EC"1.76dSm-1) and saline conditions (EG 15.30 dsm-r) on four sunflower inbred lines and tireir possible single crosses excluding reciprocals. Path coefficient analysis revealed that head diameter followed by 100-achene weight, made the highest direct contribution to achene yield under normal condi tions. Head diameter followed by K+ concentration in young growing leaves showed the highest direct effect on achene yield under saline conditions. Therefore, it is suggested that selection criteria would be different under normal and saline conditions to improve achene yield. Selection could be based on genotypes having large head diameter and higher 1O0-achene weight, under normal conditions, whereas, on large head diameter and high K+ concentration imposing restriction on Na+ concentration in young growing leaves, undér saline conditions.

The objectives of this study were to determine the geographic and ecological distribution of Helianthus, Vigtiera, and Tithonia genera in Mexico in order to preserve their species and utilize them in plant breeding and taxonomic studies. Information from the Mexican herbaria: MEXU, ENCB, and CIIDIR was used to localize the areas where wild species of Helianthus, Tithonia, and Wguiera grow. Ten species of Lantana,19 of Tithonia, and 88 of Viguiera were found. Helianthus has its main distribution surrounding the Sierra Madre Occidental and Sierra Madre Oriental highlands. Helianthus annuus has the widest distribution. The Tithonia genus is mainly distributed in the highlands, with T. nbiformis being the most abundant species in this ecological area. The Tithonia genus possibly occupies the ecological area in the highlands, as Helianthus does in the lowlands. Viguiera has the widest distribution, being found in almost all the Mexican States.

Combining ability effects of four cytoplasmic male sterile lines in combinâtion with two restorer lines were calculated by using the line x tester analysis technique at the National Agricultural Research Centre, Islamabad. The line CMS-HA-89 was the best general combiner for yield, oil content, and 100-achene weight. The restorer RHA-271 was a better general combiner as compared with RHA-273. The best specific combination for yield was CMS-HA-277 x RHA 271.

Sunflower defatted meal is a good source of protein of nutritional quality. The defatted meal of the whole seed contains about 24.02+2.27 Vo hull and 75.35+2.1,7 Vo endosperm, with an endosperm to hull ratio of 3.17+0.38. The fibre content in the defatted meal amounts to 29.83+4.03 7a, out of which 17.18+2.1,4 7o is contributed from the hull alone, and the ratio of fibre content in the hull to kernel is 1.42+0.25. The results of the germination studies indicate that there is a gradual degradation of the globulins, glutelins, and prolamines in uilro, followed by a concomitant increase in the albumins after the third day of germination. IVPD analysis shows that the fibre content has hardly any effect on the protein digestibility by pepsin + pancreatin.

Three sunflower (Helianthus annuus L.) open-pollinated varieties and one hybrid were tested in two selection cycles during 1986 and 1987. The produced populations were evaluated in 1988 in an experiment planted in the "Altiplano potosino" semiarid north central zone of México. ATOVofromeach population was selected on the following aspects: head diameter, plant height (1.40-1.60 m), black color of the seed, absence of branches with head, and disease and pest freedom. Selection was made on the basis of the best adjusted weight using the following formula: Y: Xg + (Pp-Xp). Based on the agronomic characteristics and yield components evaluated, the five best yields were found in the following genetic materials: TECMON 3 original, TECMON 3 2nd. cycle, TECMON 3 2nd. rycle, Victoria variety and D0-725 original hybrid, with the yields of about 2.252,2.577 ,2.261,2.302 and 2.583 tlha, respectively. At the same time, they were the genetic materials with the best oil content, ranging from 35.75Vo to 44.73Vo.

Larvae of the banded sunflower moth, Cochylis hospes, feed and develop within seeds of cultivated sunflowers in the northern Great Plains of the United States and Canada. This research was designed to delineate larval damage to sunflower seeds from known adult populations and develop an economic injury level (EIL) for C. hospes using field and cage studies. Calculations showed that with aerial application costs of $17.30/ha, a sunflower market price of $0.20lkg, and a plant population of 44,6001ha, the EIL was 5.9 larvae per head. A decision of whether economic damage is likely to occur is based on known populations of adult moths. The regression equation ( Y = 1.69 +23.93X) predicted a final number of mature lawae (Y) based on the average number of adults per 10 plants during daylight hours in July (X) from 1983-1985 and 1988-1989. A density of 1 adult per 56 plants resulted in an EIL of 5.9 larvae per head. Treatment is directed at larvae and is most effective when applications are made at the R5.1 sunflower growth stage. In 1990, cages infested with one adult per plant resulted in 9.3 larvae per head; cages infested with 10 adults per plant produced 55.2 mature larvae per head. The number of mature seeds damaged by feeding larvae varied from 59.6 seeds per plant. in cages with infested with 1 adult per plant, 294.3 damaged seeds per plant, and in cages with 10 adults per plant. Results were similar in 1991. The regression equation to predict mature larvae per head (Y) was based on adult infestation level (X), which was Y:7.34 + 4.60X. Thus, each adult results in L1.94 mature larvae per head. Each lawa destroyed 6.1 and 4.8 mature seeds in 1990 and 1991, respectively.

Alternaria leaf significant blight is an important disease of sunflowers in India and elsewhere, causing significant yield losses during rainy seasons. Twenty-three moderately resistant genotypes, along with 6 interspecific lines derived from Helianthus tuberosus, were evaluated under natural epiphytotic conditions. The highly susceptible line L-101 was planted along all the borders and in between as an infector and spreader of the disease. The disease severity was assessed using 0-9 numerical rating system based on the infected area of plants during the beginning of anthesis and at full maturity of crop growth. None of the genotypes tested, including interspecific lines, recorded high levels of resistance. Most of the genotypes tested were highly susceptible. Three germplasm lines, viz., 180, 873, 1229, and the hybrid ISFH-306, recorded moderate levels of resistance. The results indicate that a high level of resistance is not available in the limited cultivated germoplasm tested. An alternate strategy to utilize the available low levels of resistance to develop resistant populations is discussed.

Having established their efficiency and compatibility, the following organisms: Azotobacter chroococcurn (G A-2), Glomus fasciculatum ^nd Penicillium glaucum (HE-4) were selected to assess their combined effect on the growth and yield of sunflower in pot culture studies in greenhouse conditions, The results show that the values of growth parameters of sunflower like height, stem girth, number of leaves and leaf area were more responsive to all three organisms as compared with individual treatments. Early flowering is noticed in the treatment with Paricillium alone; leaf and stem dry weight were significantly higher than the control in all the treatments. All treatments e\cÊptAmtobacter alone resulted in significant increases in seed yield. The oil percentage was significantly over the control when test plants were inoculated with all three organisms together. However, all treatments had a positive effect on oil yield when compared with the control. Shoot nitrogen percentage was significantly increased over the control with all combinations of treatments. However, phosphorus percent did not vary in the treatments except in Glomus with Penicillium and all organisms together, where the phosphorus percent was higher than in the control. Rhizosphere study shows that the Amtobacler population was higher in the inoculated treatment. Phosphate-solubilising fungi were increased where P. melanogaster was inoculated with the other organisms. No large variations in the fungal population were noticed, whereas Glomus inoculation had stimulated the bacterial population. The percentages of mycorrhizal infection and spore production were lower in Glomus with Penicillium as compared with the other Glomus inoculation treatments.