EFFECT OF IRRIGATION INTERVALS AND NITROGEN FERTILIZER RATES ON FLAX YIELD AND SOME ANATOMICAL MANIFESTATIONS

Abstract

Two field experiments were carried out at Gemmeiza Research Station, El-Gharbia Governorate, Agricultural Research Center, Egypt, during the two successive winter seasons of 2015/2016 and 2016/2017. The objective of this work was to evaluate the effect of irrigation intervals (every 21, 28 and 35 days) and nitrogen fertilizers rates [untreated (0), 30, 45 and 60 kg N/fad] on quantity and quality of straw and seed characters of flax (Cultivar Giza 10), in addition to study anatomical manifestation in middle technical stem length. The experimental design was split-plot in three replications. Significant differences were detected for all studied traits, i.e. total plant height (cm), technical stem length (cm), upper branching zone length (cm), straw yield/plant (g), straw yield (kg/fad), total fiber percentage (%), fiber yield (kg/fad), fiber length (cm), number of capsules/plant, number of seeds/capsule, seed index (g),seed yield/plant (g), seed yield (kg/fad), biological yield (kg/fad), oil percentage (%) oil yield (kg/fad)and fiber fineness (Nm)among irrigation intervals or nitrogen fertilizer rates in the combined analysis. Irrigated flax plants every 21 days gave the maximum values for total plant height (cm), technical stem length (cm), upper branching zone length (cm), straw yield/plant (g), straw yield (kg/fad), total fiber percentage (%), fiber yield (kg/fad), fiber length (cm), number of capsules/plant, number of seeds/capsule, seed index (g), seed yield/plant (g), seed yield (kg/fad), biological yield (kg/fad), oil percentage (%) and oil yield (kg/fad) in the combined analysis. On the other hand, significantly gave the low values of fiber fineness (Nm). In contrast, irrigation every 35 days gave the minimum values for all studied characters under this study except, fiber fineness (Nm). Irrigated flax every 28 days gain intermediate estimates in all studied traits without significance with irrigation every 21days. Anatomical studies, i.e. total cross section area (mm2), cortex area (mm2), fiber area (mm2), xylem area (mm2) and pith area (mm2), fiber index (cm3), cortex % and fiber % were increased when irrigated flax plants every 21 days. But xylem % and pith % were decreased. All traits of flax under study showed significantly increased by increasing nitrogen fertilizer rates from untreated up to 60 kg N/fad, except fiber fineness (Nm) was significant decreased with increasing nitrogen rates in the combined analysis. Results reported that no significant differences between soil fertilized by 45 and 60 kg N/fad on all flax traits under study. All anatomical studies, i.e., (total cross section area (mm2), cortex area (mm2), fiber area (mm2), xylem (mm2), pith (mm2), fiber index (mm3), cortex %, fiber % and xylem %) were increased with increasing nitrogen fertilizer rates up to 60 kg N/fad, expect pith % was decreased. Results showed that irrigated flax plants every 21 days and soil fertilized by 60 kg N/fad significantly gave the maximum values of seed, biological and oil yield (kg/fad) in the combined analysis. In addition to great reduction in fiber fineness (Nm) had happened in this case. It could be concluded that planting flax plants (Giza 10) under irrigated interval every 21 or 28 days and soil fertilized by 45 or 60 kg N/fad to maximized quantity and quality of straw and seed yield characters as well as anatomical studies.