Screening And Mechanism Exploration Of Suitable Substrates For Potato Original Seed Expansion And Propagation

In this experiment,corn straw,slag,vermiculite,and peat were prepared into 7 different substrates according to different volume ratios.The potato early maturing variety"Early white"and mid late maturing variety"Yanshu4"tissue culture seedlings were used as experimental materials.The physical and chemical properties of the 7 different substrates were measured before the potato tissue culture seedlings were planted and after the original seeds were harvested.The morphological and physiological indicators of the 2 potato varieties were measured The comprehensive analysis of yield indicators and nitrogen,phosphorus,and potassium absorption aims to screen out potato original seed cultivation substrates with abundant resources and excellent performance,in order to achieve the goal of improving quality and efficiency.The main results of the experiment are as follows:（1）In different proportions of test substrates,T₄ prepared by corn straw,peat,and slag in a volume ratio of 1:3:4,and T₅ prepared by corn straw,peat,and slag in a volume ratio of2:2:2:4,have a unit weight increase of 63.04%-80.43%compared to CK（vermiculite）.The total porosity and water holding porosity are closer to CK,and the ventilation porosity increases by 33.33%-77.66%compared to CK.The water to air ratio is less than CK,and both show acidity,with a p H value of 5.27-6.76.They are alkaline hydrolyzed nitrogen and available phosphorus The content of available potassium is much higher than CK,which can provide the necessary nutrients for the growth of potato tissue culture seedlings.（2）Among the tested substrate materials,T₄ and T₅,composed of corn straw,peat,and slag,are more suitable for the growth of potato tissue culture seedlings.The morphological indicators of potato tissue culture seedlings include plant height,larger stem diameter,more leaf numbers,and higher above ground and underground fresh weights than CK during the period.In the physiological indicators of potato tissue culture seedlings,not only did the root activity increase,but also the chlorophyll a content,chlorophyll b content,and total chlorophyll content were relatively higher,with chlorophyll content basically higher than CK.As time went on,the cumulative absorption of nitrogen,phosphorus,and potassium in tissue cultured seedlings gradually increased.The nitrogen and phosphorus content was higher in the period than CK,and the potassium content increased by 4.61%-37.11%compared to CK.（3）In different ratios of substrates,the survival rates of"Early white"and"Yanshu4"tissue cultured seedlings in T₄ and T₅ after 14 days of planting were 8.50%-13.47%higher than CK,and were all higher than T₁（corn straw:peat:vermiculite=1:3:4）,T₂（corn straw:peat:vermiculite=2:4）,T₃（corn straw:peat:vermiculite=3:1:4）,T₆（corn straw:peat:vermiculite=3:1:4）ratio substrates.Through comprehensive comparison,The average number of tubers per plant in the tissue culture seedlings of"Early white"and"Yanshu4"potatoes is moderate,with larger average single tuber weight,maximum single tuber weight,and minimum single tuber weight.The large tuber rate is 11.72%-20.56%higher than CK.Except for T₄’s"Early white"with a maximum single tuber weight slightly less than CK,T₅’s"Early white"with a minimum single tuber weight slightly less than CK,all other yield indicators are higher than CK,and"Yanshu4"with a yield indicator higher than CK.In summary,under the conditions of this experiment,when the ratio of corn straw,peat,and slag is between 1:3:4 and 2:2:4,it can significantly promote the growth and development of potato tissue culture seedlings.The matrix materials used in the experiment are not only abundant in resources,but also have excellent performance compared to traditional matrix materials such as vermiculite and peat.