Simazine and prometryne applied to the soil surface in pots at 1-6 and 3-2 kg/ha. 2 days after sowing, did not affect germination or early seedling growth of chickpea. Reductions were noticed under all treatments in the leaf dry weight after 28 days and in the length of the main stem after 42 days. Dry-matter accumulation in the shoot was drastically reduced with simazine but not with prometryne. All treatments retarded dry-matter accumulation in the roots with time. Prometryne reduced chlorophyll content during early growth stages and simazine during later stages.Growth of the rhizobial culture was reduced with increasing concentrations (1-20 mg/1) of both simazine and prometryne. Root nodule initiation was not affected by either of the herbicides but the later production of new nodules and growth of the nodules were reduced in different degrees by various treatments. Overall nodulation was drastically reduced with simazine. Reductions in nodulation with simazine and prometryne appeared to be primarily a case of general root growth reduction. The pink pigment, leghaemoglobin, did not develop at all in the nodules of simazinetreated plants and its concentration was not affected in the nodules of prometrynetreated plants. The N 2 -fixing efficiency (acetylene reduction) of the nodules was more in the case of prometryne-treated plants and was nil in the case of simazine-treated ones. INTRODUCTIONcontent 0-25 %), 3 kg/pot. The soil was brought to field capacity and chickpea (Cicer arietinum L.), Chickpea is one of the important pulse crops of cv. H-208, seeds inoculated with rhizobial strain arid and semi-arid regions of the world. Simazine Ca 164, were sown, ten per pot, at a depth of 3 cm. and prometryne are amongst the list of herbicides Two days after sowing, simazine and prometryne tried and have been found to control effectively were applied to the soil surface at 1-6 and 3-2 kg the main weeds in this crop. There are indications (a.i.)/ha. Filtered canal water was used for all that the concentrations of simazine and prometryne treatments as well as for irrigation. The experiment which reduce dry-matter production in crop plants was conducted outdoors under net house conditions also reduce the number and weight of the root using a completely randomized design, nodules (Elenkov et al. 1970; Hauke-Pacewiczowa, Germination counts were taken daily. Thinning 1970; Mishra & Gaur, 1974; Thomas & Hammond, was carried out from time to time to leave four 1968;Vagina & Latypova, 1972). However, none plants of similar growth in each pot. Three pots at of these studies showed whether the herbicide acted random from each treatment were sampled 14, 28, directly on the process of nodulation or indirectly 42 and 56 days after sowing. At each time, the root through general plant growth suppression. There-system was gently removed from the soil in running fore in the present investigations, an attempt was tap water without loss of any roots or nodules, made to study the process of nodulation as distinct The root system of plants ...

Summary: Résumé: Zusammenfassung Vicia sativa (L.) was subjected to pre‐emergence treatments of alachlor, fluchloralin, nitrofen and prometryne. A study of stomatal index was made by collecting leaves from the fourth and fifth nodes of plants. Nitrofen and prometryne, although increasing the number of epidermal cells and stomata per unit area, did not lead to changes in the stomal index compared to control values. Alachlor and fluchloralin reduced the stomatal index greatly because the density of epidermal cells was increased more than the density of stomata. The results are discussed. Effet de quelques herbicides sur l'épiderme de Vicia sativa (L.) Vicia sativa (L.) a été soumise à des traitements en prélevée avec l'alachlor, la fluchloraline, l'azote et la prométryne. Une étude de l'index stomatal a été faite en récoltant des feuilles sur les quatriéme et cinquiéme nœuds des plantes. L'azote et la prométryne, bien que provoquant un accroissement du nombre des cellules épidermiques et des stomates par unité de surface, n'ont pas amené de changement de l'index stomatal comparativement aux valeurs du témoin. L'alachlor et la fluchloraline ont fortement réduit l'index stomatal parce que la densité des cellules épidermiques s'est plus accrue que la densité des stomates. Les résultats sont discutés. Effet de quelques herbicides sur l'épiderme de Vicia sativa (L.) Vicia saliva (L.) a été soumise à des traitements en prélevée avec l'alachlor, la fluchloraline, l'azote et la prométryne. Une étude de l'index stomatal a été faite en récoltant des feuilles sur les quatrième et cinquième nceuds des plantes. L'azote et la prométryne, bien que provoquant un accroissement du nombre des cellules épidermiques et des stomates par unité de surface, n'ont pas amené de changement de l'index stomatal comparativement aux yaleurs du témoin. L'alachlor et la fluchloraline ont fortement réduit l'index stomatal parce que la densité des cellules épidermiques s'est plus accrue que la densité des stomates. Les résultats sont discutés. Die Wirkung einiger Herbizide auf die Epidermis von Vicia sativa (L.) Alachlor, Fluchloralin, Stickstoff und Prometryn wurden vor dem Auflaufen von Vicia sativa (L.) appliziert. Um den Stomataindex festzustellen, wurden Blätter vom 4 und 5 Nodium entnommen. Die Stickstoff‐ und Prometrynbehandlungen bewirkten zwar eine Zunahme der Epidermiszellen und der Stomata je Flächeneinheit, hatten aber im Vergleich zur Kontrolle keine Veränderungen des Slomataindex zur Folge. Alachlor und Fluchloralin verkleinerten den Stomataindex sehr stark, da die Dichte der Epidermiszellen stärker zunahm als die Dichte der Stomata. Die Ergebnisse werden diskutiert.