We made S1 and testcross progeny evaluations for two cycles of recurrent selection for grain yield in a 13‐line maize (Zea mays L.) synthetic. In the first cycle we evaluated 60 lines at four locations in 1 year. For the second cycle we evaluated 68 lines in three trials during 2 years. Selection intensity was 17% in both cycles.Genetic variance for grain yield in the first cycle was significantly greater for selfed progeny in comparison with testcross evaluation, but decreased in the second cycle. Variability for ear moisture, broken stalks, and root lodging was increased with both selection procedures. S1 selection for grain yield gave greater improvement in the population per se, and was equal to testcross selection for general combining ability improvement. However, one second‐cycle testcross progeny exceeded the highest‐yielding parental line testcross.Genotypic correlations were greater between related and nonrelated testcrosses than between S1 and either testcross. However, several selections were common to both S1 and testcross procedures. Second‐cycle correlations were significantly lower than first‐cycle values.

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Root and stem extracts of Fumaria parviflora showed strong nematicidal activity against Meloidogyne incognita in in vitro and in planta experiments. Phytochemical screening of F. parviflora revealed the presence of seven classes of bioactive compounds (alkaloids, flavonoids, glycosides, tannins, saponins, steroids and phenols). Quantitative determination of the plant extracts showed the highest percentages of alkaloids (0AE9 ± 0AE04) and saponins (1AE3 ± 0AE07) in the roots and total phenolic contents in the stem (16AE75 ± 0AE07 lg dry g)1). The n-hexane, chloroform, ethyl acetate and methanol extracts of roots and stems at concentrations of 3AE12, 6AE24, 12AE5, 25AE0 and 50AE0 mg mL , significantly inhibited hatching and increased mortality of second-stage juveniles (J2s) compared with water controls. Percentage J2 mortality and hatch inhibition were directly related to exposure time. In pot trials with tomato cv. Rio Grande, root and stem extracts at concentrations of 1000, 2000 and 3000 ppm, applied as soil drenches, significantly reduced the number of galls, galling index, eggs masses, eggs and reproduction factor compared with the water control. Regardless of concentration, all the extracts significantly increased the host plant growth parameters studied. The n-hexane extracts from the roots and stem were the most active, followed by the methanol ones, at all concentrations. The in vitro and in planta results suggest that extracts from the roots and stem of F. parviflora may be potential novel nematicides.

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