Effect Of Rice Straw Mulching And PAM On Growth And Yield Of Autumn Sticky Maize In Hilly Red Soil Upland

In this experiment, with sticky maize as an indicator crop under rice straw mulching and polyacrylamide (PAM) appling for water-saving in hilly red soil upland, designed under five treatments (A:CK; B:furrowing 30 kg/hm2 of PAM; C:mulching 5000 kg/hm2 of rice straw; D:furrowing 30 kg/hm2 of PAM + mulching 5000 kg/hm2 of rice straw; E: furrowing 60 kg/hm2 of PAM) were implemented, the soil moisture, nutrient status, together with the growth process individual growth status, physiological indicators, yield and biomass of the sticky maize were investigated.and the results were as follows:(1) When rice straw was mulched and PAM was applied, the rainfall could be accepted, retained and saved by soil, and the evaporation of soil moisture could be reduced in the case of drought, as a result the soil water content was increased. Under sunning 2d after consecutive rains, the soil moisture of 0～20cm deep below soil surface in the treatment B, C, D, E was 0.78%,1.10%,1.42%and 0.98% higher than that in treatment A (CK), respectively; Under sunning 5d after consecutive rains, the soil moisture of 0～20cm deep below soil surface in the treatment B, C, D, E was 0.91%,0.99%,1.50% and 1.33% higher than that in treatment A (CK), respectively; Under sunning 10d after consecutive rains, the soil moisture of 0～20cm deep below soil surface in the treatment B, C, D, E was 0.72%, 1.20%,1.26% and 0.76% higher than that in treatment A (CK), respectively; Under sunning 18d after consecutive rains, the soil moisture of 0～20cm deep below soil surface in the treatment B, C, D, E was 1.37%,1.87%,2.40% and 1.72% higher than that in treatment A (CK), respectively. When rice straw was mulched and PAM was applied, the soil moisture of 20～40cm deep below soil surface in different treatments was all higher than A (CK), but the changes was smaller than that in 0～20cm deep below soil surface.(2) Fertilization in maize consistent throughout the case, test the soil pH value addition processing A (CK) decline, as compared with other treatments before testing pH value increases, the following order treatment D> C> E> B> A (CK); Straw mulch treatment significantly increased soil organic matter content, organic matter content in which to deal with the D largest increase over baseline (6.27%), followed by treatment C (5.18%), while the application of PAM in handling and processing of B E increased less organic matter, respectively before the test, compared with 0.82% and 0.54%, treatment A (CK) 1.09% reduced organic matter, straw mulching treatment relative to the application of super absorbent polymers to increase soil organic matter content is higher, possibly because of straw covered by the nutrient after decomposition the results into the soil; All in all treatments were higher than N are improved before the trial, in which up to deal with D (20.62%), followed by treatment C (14.43%), application of PAM treatment increased by the same B and E (10.31%); Hydrolysis of each treatment available N, P and K content than before the test has increased to some extent, the same sort to deal with treatment D> C> E> B> A (CK).(3) When PAM application and rice straw mulching, plant growth was relatively normal, and the plant height was significantly higher than that in CK. The differences of plant height continued to expand after the jointing stage, and the final plant height in mature was D>E>C>B>A(CK). When rice straw mulching and PAM application in sticky maize, the soil moisture was higher than that in CK, which could promote root development. As a result, the plant root number increased from 1 to 8, and the root length increased 0.5～6.0cm, which expanded the root absorption area and promoted the plant resilience.(4) When PAM application and rice straw mulching to sticky maize, the bald head was reduced, and the ear length, ear diameter, kernels in ear row and double ear percentage were increased. The double ear percentage under treatment C, D, E had significant difference to treatment A(CK), and treatment B and A(CK) were significantly different; Treatment C and D with rice straw mulching was significantly shorter than treatment A(CK).(5) Rice straw mulching and PAM application could improve the sticky maize biomass. In all treatments, D had the highest biomass, which was 36200.0 kg/hm2 and 27.2% higher than treatment A(CK); The biomass of treatment C was higher, which was 35566.7 kg/hm2 and had a 25.0% of increasement; The biomass of treatment E and B was 32300.0 kg/hm2 and 31766.7 kg/hm2, which was 13.5% and 11.7% higher than treatment A(CK). The latter biomass between treatment D and treatment C had little difference, but they were significant to CK; PAM was applied to treatment E and B, their late biomass were close. The biomass of treatment E and B increased by more than 10%, but they were not significant to CK.(6) Rice straw mulching and PAM application could improve the yield of sticky maize. The yield of treatment D (10533.3 kg/hm2) was the highest, which was 37.4% higher than treatment A(CK); The yield of treatment C was higher, which was 9466.7 kg/hm2 and had a 23.5% of increasement; The yield of treatment E and B was 9016.7kg/hm2 and 8833.3 kg/hm2, which was 17.6% and 15.2% higher than treatment A (CK). Treatment D and A (CK) between the 1% significant difference, while with treatment B and E between the 5% significant difference, and treatment C was no significant difference; treatment C and A (CK) between the 5% significant difference, treatment B, E and A (CK) were not significantly different.