«EFFECT OF DROUGHT STRESS ON YIELD OF A DETERMINATE CULTIVAR OF BLUE LUPINE GROWN IN PURE SOWING AND IN MIXTURE WITH BARLEY Janusz Podle ny, Anna ...»
Acta Sci. Pol., Agricultura 9(3) 2010, 61-74
EFFECT OF DROUGHT STRESS ON YIELD
OF A DETERMINATE CULTIVAR
OF BLUE LUPINE GROWN IN PURE SOWING
AND IN MIXTURE WITH BARLEY
Janusz Podle ny, Anna Podle na
Institute of Soil Science and Plant Cultivation – National Research Institute
in Puáawy 1
Abstract. The study was carried out in 2007-2009 at the growth chamber of the Institute of Soil Science and Plant Cultivation – National Research Institute in Puáawy, in Mitscherlich pots containing a mixture of 5 kg of hortisol and 2 kg of sand. 1st order factor was soil
moisture: 30 and 60% of field water capacity (FWC), and 2nd order factor – a way of sowing:
pure sowing of lupine – 5 plants, mixed sowing – 3 lupine plants and 6 barley plants and pure sowing of barley – 10 plants·pot-1. Blue lupine of the cultivar Sonet and barley of the cultivar Johan were sown in the experiment. The aim of this study was to estimate the response of a determinate cultivar of blue lupine grown in pure sowing and in mixture with barley to drought stress occurring in the flowering period. A lower sensitivity to drought of the lupine-barley mixture than of lupine cultivated in pure sowing was observed. Under conditions of the optimal soil moisture (60% FWC) sowings of lupine with barley gave the highest yield, whereas under conditions of water deficiency in soil barley grown in pure sowing gave the highest yield. For the reason of a larger yielding stability, under conditions of expected water deficiency in soil it is better to cultivate blue lupine with barley than in pure sowing. Planing such sowings, it should be taken into account that in spite of high yields they provide less lupine seeds than pure sowings of this species.
Key words: lupine protein, root yield, leaf area, SPAD, soil moisture
INTRODUCTIONInter-species mixture cultivation, including legume-cereal mixtures, is a long- established agricultural practice which allows rational utilization of the natural environmental resources. Species diversity results in a compensating growth and development of the cultivated species, a decrease in spreading diseases and pests, as Corresponding author – Adres do korespondencji: prof. dr hab. Janusz Podle ny, Department of Forage Crop Production of Institute of Soil Science and Plant Cultivation – National Research Institute in Puáawy, Czartoryskich 8, 24-100 Puáawy, e-mail: firstname.lastname@example.org J. Podle ny, A. Podle na 62 well as reduction in weed infestation [Martin 1982, Gaá zewski 2006a, Poetsch 2006].
Mixtures of spring cereals with legumes play a crucial role in integrated and ecological production system [Noworolnik 2000, Ksi ak i Borowiecki 2001], where the care of the soil environment is of particular importance. Unfavorable course of the weather conditions, including mainly precipitation shortage, especially at the flowering stage, constitutes one of the most important factors limiting legume plant yielding [Xia 1997, Baigorri et al. 1999, Costa-Franca et al. 2000, Barrios et al. 2005, Podle ny and Koco 2006]. The breeding work resulted in obtaining genotypes of blue lupine of determined growth, earlier and even ripening, often referred to as determinate [Prusi ski 2007]. The studies carried out to date the most often estimated the response of various cultivars and species of lupine cultivated in pure sowing to water deficiency in soil [Grzesiak et al.
1997, Podle ny 2001, Podle ny and Podle na 2003]. Nevertheless, there are no results of studies indicating the response of determinate cultivars of blue lupine in mixed sowings with cereals to periodical water deficiencies in soil. This question is of growing importance, since in recent years, long drought periods occur more and more often in spring and summer months in our country [àab dzki and Le ny 2008]. From the research conducted so far it follows that the yields of lupine-cereal mixtures are higher and more stable in the years than the mean yields of the suitable cereals and lupines in pure sowings [Rudnicki and Kotwica 2007]. This may result from a higher resistance of this type of sowings to drought stress, determined by a better utilization of water by different root systems of both species composing the mixture.
The aim of this study was to estimate the response of the determinate cultivar of blue lupine Sonet cultivated in pure sowing and in mixture with barley to drought stress occurring in the flowering period.
MATERIAL AND METHODS
The study was carried out in 2007-2009 at the growth chamber of the Institute of Soil Science and Plant Cultivation – National Research Institute in Puáawy, in Mitscherlich pots containing a mixture of 5 kg of hortisoil and 2 kg of sand. Factor I of the experiment was soil moisture: 30 and 60% of field water capacity (FWC), varied in
flowering and pod formation periods, and factor II order factor – the sowing method:
pure sowing of lupine – 5 plants, mixed sowing – lupine plants and 6 barley plants and pure sowing of barley – 10 plants·pot-1. Blue lupine of the cultivar Sonet and barley of the cultivar Johan were sown in the experiment. Before sowing the seeds were dressed with the preparation Sarfun T 450 FS (a.s. carbendazim, tiuram). The seeds sown were characterized by a high germinating capacity, amounting to 94% for lupine and 98% for barley. At the flowering stage the plants were treated once with the fungicide Sarfun 500 SC (a.s. carbendazim). Aphids were controlled with the preparation Pirimor 500 WG (a.s. pirimicarb). The fertilization applied was as follows (g·pot-1): N – 0.3, P – 1.1 and K – 1.4. A precise irrigation appliance with a fertilizer dispenser was applied for soil watering and plant fertilization. The basic element of this appliance is a programmer which starts electromagnetic valves of particular sections of the irrigation system, according to the amount of the water needed. The amount of water necessary to maintain 30 and 60% FWC was determined with the weighing method, each time before programming the irrigation appliance. Fertilizers were applied in the liquid form during watering, at two dates – after emergence and at the stage of 1-2 lupine leaves. Detailed
Acta Sci. Pol.Effect of drought stress... 63
observations of plant growth and development were conducted during the growing period. Measurements of plant height were made and the occurrence of diseases and pests were determined at several more important developmental stages. At the pod setting and seed filling stages, the leaf area was measured with the apparatus LI 3050A and the leaf greenness index with the apparatus N-Tester SPAD 502. During harvest at the full maturity stage, it was determined as follows: on the lupine plants – the number of pods and seeds, the weight of seeds and their moisture, thousand seed weight (TSW);
and on the barley plants – the shoot number, the ear number, the number of grains per ear, the grain weight and their moisture and thousand grain weight (TGW). The results of the study constituting means from 3 pots were worked out statistically with the analysis of variance method, using Tukey’s confidence half-interval at the significance level P = 0.05. Statistical calculations were made using the program Statgraphics Plus 5.
RESULTS AND DISCUSSION
Since the seeds sown were characterized by a very good seed quality, the emergence of lupine and barley plants were very even and occurred after 6 days from sowing. No differences were found between the course of plant emergence in pure and mixed stands. No occurrence of diseases and pests of lupine and barley appearing at the seedling stage were observed. The sowing method significantly influenced the growth and development of the plants. The first differences in the course of plant development stages were observed at the flowering stage. Blue lupine cultivated with barley came into flower 3 days earlier than that cultivated in pure sowing. A change in the date of the start and the duration of the phenological phases of plants cultivated in inter-species mixtures was also observed in previous studies concerning cultivation of pea with wheat [Podle ny 1994] and yellow lupine with spring triticale [Kotecki et al. 2001]. Legumes growing in the vicinity of cereals are exposed to an increased competition for light, water and nutrients, which leads to their accelerated generative development. The sowing method modified also the height of lupine and barley plants. Differences in the height of plants cultivated in pure and mixed sowing observed at the flowering stage remained until the full maturity stage (Table 1). Plants of blue lupine and barley cultivated in mixed stands reached a significantly smaller height as compared with those cultivated in pure sowing. This relation applied to both plants growing under conditions of drought stress and at the optimal soil moisture. A reduction in plant height due to mixed sowing for lupine plants growing under conditions of water deficiency in the soil and under the optimal conditions was 23.8 and 31.3%, respectively. For barley the values of those indexes amounted to 3.8 and 4.0%, respectively. Shortening of the height of yellow lupine plants growing in mixture with triticale was reported by Kotecki et al.  also in field experiments. This confirms the opinion that relations occurring in pot experiments, are very often observed under conditions of field experiments. The study by Bieniaszewski et al. [2003a] indicated that the reduction in the height of plants cultivated in mixture, resulting from water deficiency in the soil, is different at particular phenological phases of plants. A decrease in plant height caused by water deficiency is larger at budding, flowering or pod setting than at maturing. Also Wanic et al.  indicated that the competitiveness of cereals in relation to field peas is the highest at the ear formation stage and it decreases at the final stage of plant ontogenesis.
Table 1. Value of selected characters of lupine and barley plants depending on the sowing method and soil moisture Tabela 1.
Warto ü wybranych cech ro lin áubinu i j czmienia w zale no ci od sposobu siewu i wilgotno ci gleby
Cultivation of lupine with barley had a limiting effect on the size of leaf area of both species. A decrease in the leaf area of lupine and barley cultivated in mixture as compared with their pure stands amounted to 17.9 and 6.8%, respectively and was higher under unfavorable conditions of soil moisture. A reduction in the leaf area of lupine and barley owing to their cultivation under conditions of water deficiency in the soil was 59.8 and 15.5%. A decrease in leaf area caused by water deficit in the soil was also reported by Barrios et al.  with reference to another legume – bean. The authors also indicated that water deficiency in the soil reduces the area of leaves occurring on lateral shoots by 60.1%, whereas the area of leaves occurring on the main stem of the plant was reduced only by 10.4%.
The sowing method and soil moisture modified also the value of the leaf greenness index SPAD, which reflects chlorophyll content in leaves. Both lupine and barley plants cultivated on the soil with a higher moisture were characterized by a larger value of the SPAD index than the plants growing under conditions of periodical water deficiency in the soil. Cultivation in mixture resulted in a decrease in the value of the leaf greenness index SPAD of lupine and an increase in the value of this index for barley. Probably the vicinity of a legume had an effect on nutrition of the cereal with nitrogen. These conjectures are confirmed by the study [Triboi 1985] which indicates that cereals cultivated with legumes can take up considerable amounts of fixed nitrogen. The process of biological nitrogen fixation and its moving from the legume to the cereal plant is widely described also by Fujita et al. . Kotecki et al. [2003b], in turn, reported that triticale cultivated with yellow lupine was more green and its growth was
Acta Sci. Pol.Effect of drought stress... 65
prolonged by 3-4 days in relation to that cultivated in pure sowing, which also can prove a better nutrition with nitrogen. The results obtained are not confirmed by the study by Olszewska , who showed that water deficit in the soil results in a growth of chlorophyll content in leaves of white clover and a decrease in photosynthesis intensity. According to the author, not all the chlorophyll contained in the plant takes part in the process of photosynthesis, but its considerable amount can play other functions, for instance defensive. Therefore, the plants exposed to stress probably contain its larger amounts. A change in chlorophyll content in leaves caused by drought stress may have a species, and even varietal, character.
Periodical water deficiency in the soil and the sowing method had a significant effect on the height of yield of plant vegetative and generative organs. Under conditions of the optimal soil moisture, of all the cultivation variants, the highest seed yields were obtained from stands of lupine with barley, whereas under conditions of water deficiency in the soil, barley cultivated in pure sowing gave the highest yield (Fig. 1).
Kotecki et al. [2003a], conducting a field study concerning the cultivation of yellow lupine with triticale, under unfavorable weather conditions obtained also the highest seed yields from cultivation of triticale in pure sowing, and the lowest from the cultivation of lupine in pure sowing.
Fig. 1. Seed yield of blue lupine and barley grain depending on the cultivation system and soil moisture Rys. 1. Plon nasion áubinu w skolistnego i ziarna j czmienia w zale no ci od sposobu uprawy i wilgotno ci gleby The largest reduction in yield of lupine seed and barley grain owing to drought occurring at the flowering stage was observed on the treatments with mixed stands, and the smallest decrease in yield on the treatment with pure stands of those species.